Form 8-K

8-K — AMERICAN TOWER CORP /MA/

Accession: 0001053507-26-000145

Filed: 2026-09-18

Period: 2026-09-17

CIK: 0001053507

SIC: 6798 (REAL ESTATE INVESTMENT TRUSTS)

Item: Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers: Compensatory Arrangements of Certain Officers

Item: Other Events

Item: Financial Statements and Exhibits

Documents

8-K — amt-20260917.htm (Primary)

EX-99.1 (exhibit9912026q3dividend.htm)

GRAPHIC (image_0.jpg)

XML — IDEA: XBRL DOCUMENT (R1.htm)

8-K

8-K (Primary)

Filename: amt-20260917.htm · Sequence: 1

amt-20260917

AMERICAN TOWER CORP /MA/0001053507false00010535072026-09-172026-09-170001053507exch:XNYSus-gaap:CommonStockMember2026-09-172026-09-170001053507exch:XNYSamt:A0450SeniorNotesDue2027Member2026-09-172026-09-170001053507exch:XNYSamt:A0400SeniorNotesDue2027Member2026-09-172026-09-170001053507exch:XNYSamt:A4125SeniorNotesDue2027Member2026-09-172026-09-170001053507exch:XNYSamt:A0500SeniorNotesDue2028Member2026-09-172026-09-170001053507exch:XNYSamt:A0875SeniorNotesDue2029Member2026-09-172026-09-170001053507exch:XNYSamt:A0950SeniorNotesDue2030Member2026-09-172026-09-170001053507exch:XNYSamt:A3.900SeniorNotesDue2030Member2026-09-172026-09-170001053507exch:XNYSamt:A4625SeniorNotesDue2031Member2026-09-172026-09-170001053507exch:XNYSamt:A1.000SeniorNotesDue2032Member2026-09-172026-09-170001053507exch:XNYSamt:A3.625SeniorNotesDue2032Member2026-09-172026-09-170001053507exch:XNYSamt:A1250SeniorNotesDue2033Member2026-09-172026-09-170001053507exch:XNYSamt:A4.000SeniorNotesDue2033Member2026-09-172026-09-170001053507exch:XNYSamt:A4.100SeniorNotesDue2034Member2026-09-172026-09-17

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON D.C. 20549

FORM 8-K

CURRENT REPORT PURSUANT

TO SECTION 13 OR 15(d) OF THE

SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of Earliest Event Reported): September 17, 2026

AMERICAN TOWER CORPORATION

(Exact Name of Registrant as Specified in Charter)

Delaware

001-14195

65-0723837

(State or Other Jurisdiction of Incorporation)

(Commission File Number)

(I.R.S. Employer Identification No.)

222 Berkeley Street

Boston, Massachusetts 02116

(Address of Principal Executive Offices) (Zip Code)

(617) 375-7500

(Registrant's telephone number, including area code)

Not Applicable

(Former name or former address, if changed since last report.)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading Symbol(s) Name of each exchange on which registered

Common Stock, $0.01 par value AMT New York Stock Exchange

0.450% Senior Notes due 2027 AMT 27C New York Stock Exchange

0.400% Senior Notes due 2027 AMT 27D New York Stock Exchange

4.125% Senior Notes due 2027 AMT 27F New York Stock Exchange

0.500% Senior Notes due 2028 AMT 28A New York Stock Exchange

0.875% Senior Notes due 2029 AMT 29B New York Stock Exchange

0.950% Senior Notes due 2030 AMT 30C New York Stock Exchange

3.900% Senior Notes due 2030 AMT 30D New York Stock Exchange

4.625% Senior Notes due 2031 AMT 31B New York Stock Exchange

1.000% Senior Notes due 2032 AMT 32 New York Stock Exchange

3.625% Senior Notes due 2032 AMT 32B New York Stock Exchange

1.250% Senior Notes due 2033 AMT 33 New York Stock Exchange

4.000% Senior Notes due 2033 AMT 33D New York Stock Exchange

4.100% Senior Notes due 2034 AMT 34A New York Stock Exchange

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.☐

Item 5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

(d) On September 17, 2026, the Board of Directors (the “Board”) of American Tower Corporation (the “Company”) elected Kristen M. Ludgate as a director and member of its Compensation and Human Capital Committee, effective immediately. In accordance with the Company’s Amended and Restated By-Laws, Ms. Ludgate will serve as a director until the Company’s 2027 Annual Meeting of Stockholders and until her successor is duly elected and qualified.

Ms. Ludgate most recently served as Chief People Officer of HP Inc., a global technology company, from 2021 to 2025, where she led culture, talent and organizational strategies to accelerate the company's transformation and worked closely with HP's chief executive officer and board of directors on succession, compensation and corporate strategy. Prior to HP, Ms. Ludgate spent over 15 years at 3M Company, where she held two c-suite roles, as Executive Vice President and Chief Human Resources Officer and as Senior Vice President, Communications and Enterprise Services, as well as executive leadership roles in Legal, Compliance and Human Resources.

Ms. Ludgate has extensive experience in governance, risk management, talent strategy and enterprise transformation, advising chief executive officers and boards of directors on strategic and operational matters. Ms. Ludgate currently serves on the board of directors of Associated Banc-Corp (Associated Bank), where she chairs the Compensation and Benefits committee, and previously served on the board of directors of OpenText Corporation.

For her service on the Board, Ms. Ludgate will receive the Company’s standard compensation for non-employee directors.

A copy of the Press Release (“Press Release”) announcing the appointment of Ms. Ludgate to the Board is is filed herewith as Exhibit 99.1.

Item 8.01 Other Events.

On September 18, 2026, the Company issued a press release announcing that the Board declared a cash distribution of $1.79 per share on shares of the Company’s common stock, payable on October 20, 2026 to the stockholders of record at the close of business on September 30, 2026.

A copy of the Press Release is filed herewith as Exhibit 99.1.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

Exhibit No. Description

99.1

Press Release, dated September 18, 2026.

104 Cover Page Interactive Data File (embedded within the Inline XBRL document).

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

AMERICAN TOWER CORPORATION

(Registrant)

Date: September 18, 2026 By: /s/ Rodney M. Smith

Rodney M. Smith

Executive Vice President, Chief Financial Officer and Treasurer

EX-99.1

Filename: exhibit9912026q3dividend.htm · Sequence: 2

Document

Exhibit 99.1

Contact: Spencer Kurn

Senior Vice President, Investor Relations

Telephone: (617) 375-7517

AMERICAN TOWER CORPORATION ANNOUNCES ELECTION OF KRISTEN M. LUDGATE TO BOARD OF DIRECTORS AND DECLARES QUARTERLY DISTRIBUTION

Boston, Massachusetts — September 18, 2026 — American Tower Corporation (NYSE: AMT) announced that its Board of Directors has elected Kristen M. Ludgate as a director.

“We are pleased to welcome Kristen to our Board of Directors,” said Steve Vondran, President and Chief Executive Officer of American Tower. “Kristen’s decades of experience advising global organizations on governance, strategy, talent and transformation, combined with her extensive public company board experience, make her a strong fit with our Core Principles. Her broad and relevant background will provide valuable insight as we continue to advance our long-term growth strategy and deliver durable value for our shareholders.”

In addition, the Company's Board of Directors has declared a quarterly cash distribution of $1.79 per share on shares of the Company’s common stock. The distribution is payable on October 20, 2026 to the stockholders of record at the close of business on September 30, 2026.

About American Tower

American Tower, one of the largest global REITs, is a leading independent owner, operator and developer of multitenant communications real estate with a portfolio of over 148,000 communications sites and a highly interconnected footprint of U.S. data center facilities. For more information about American Tower, please visit www.americantower.com.

Cautionary Language Regarding Forward-Looking Statements

This press release contains “forward-looking statements” concerning the Company’s goals, beliefs, expectations, strategies, objectives, plans, future operating results and underlying assumptions and other statements that are not necessarily based on historical facts. Actual results may differ materially from those indicated in the Company’s forward-looking statements as a result of various factors, including those factors set forth under the caption “Risk Factors” in Item 1A of its most recent annual report on Form 10-K, and other risks described in documents the Company subsequently files from time to time with the

Securities and Exchange Commission. The Company undertakes no obligation to update the information contained in this press release to reflect subsequently occurring events or circumstances.

###

GRAPHIC

Filename: image_0.jpg · Sequence: 7

Binary file (21504 bytes)

Download image_0.jpg

XML — IDEA: XBRL DOCUMENT

XML

Filename: R1.htm · Sequence: 9

v3.26.3

Cover Cover

Sep. 17, 2026

Entity Information [Line Items]

Document Type

8-K

Document Period End Date

Sep. 17, 2026

Entity Incorporation, State or Country Code

Entity File Number

001-14195

Entity Tax Identification Number

65-0723837

Entity Address, Address Line One

222 Berkeley Street

Entity Address, City or Town

Boston

Entity Address, State or Province

Entity Address, Postal Zip Code

02116

City Area Code

617

Local Phone Number

375-7500

Written Communications

false

Soliciting Material

false

Pre-commencement Tender Offer

false

Pre-commencement Issuer Tender Offer

false

Entity Emerging Growth Company

false

Entity Registrant Name

AMERICAN TOWER CORP /MA/

Entity Central Index Key

0001053507

Amendment Flag

false

NEW YORK STOCK EXCHANGE, INC. | Common Stock

Entity Information [Line Items]

Title of 12(b) Security

Common Stock, $0.01 par value

Trading Symbol

AMT

Security Exchange Name

NYSE

NEW YORK STOCK EXCHANGE, INC. | Zero Point Four Five Zero Percent Senior Notes, Due 2027

Entity Information [Line Items]

Title of 12(b) Security

0.450% Senior Notes due 2027

Trading Symbol

AMT 27C

Security Exchange Name

NYSE

NEW YORK STOCK EXCHANGE, INC. | Zero Point Five Zero Percent Senior Notes Due 2028 [Member]

Entity Information [Line Items]

Title of 12(b) Security

0.500% Senior Notes due 2028

Trading Symbol

AMT 28A

Security Exchange Name

NYSE

NEW YORK STOCK EXCHANGE, INC. | One Point Zero Percent Senior Notes Due 2032

Entity Information [Line Items]

Title of 12(b) Security

1.000% Senior Notes due 2032

Trading Symbol

AMT 32

Security Exchange Name

NYSE

NEW YORK STOCK EXCHANGE, INC. | Zero Point Eight Seven Five Percent Senior Notes, Due

Entity Information [Line Items]

Title of 12(b) Security

0.875% Senior Notes due 2029

Trading Symbol

AMT 29B

Security Exchange Name

NYSE

NEW YORK STOCK EXCHANGE, INC. | One Point Two Five Zero Percent Senior Notes, Due 2033

Entity Information [Line Items]

Title of 12(b) Security

1.250% Senior Notes due 2033

Trading Symbol

AMT 33

Security Exchange Name

NYSE

NEW YORK STOCK EXCHANGE, INC. | 0.400% Senior Notes Due 2027

Entity Information [Line Items]

Title of 12(b) Security

0.400% Senior Notes due 2027

Trading Symbol

AMT 27D

Security Exchange Name

NYSE

NEW YORK STOCK EXCHANGE, INC. | 0.950% Senior Notes Due 2030

Entity Information [Line Items]

Title of 12(b) Security

0.950% Senior Notes due 2030

Trading Symbol

AMT 30C

Security Exchange Name

NYSE

NEW YORK STOCK EXCHANGE, INC. | 4.125% Senior Notes due 2027

Entity Information [Line Items]

Title of 12(b) Security

4.125% Senior Notes due 2027

Trading Symbol

AMT 27F

Security Exchange Name

NYSE

NEW YORK STOCK EXCHANGE, INC. | 4.625% Senior Notes Due 2031

Entity Information [Line Items]

Title of 12(b) Security

4.625% Senior Notes due 2031

Trading Symbol

AMT 31B

Security Exchange Name

NYSE

NEW YORK STOCK EXCHANGE, INC. | 3.900% Senior Notes Due 2030

Entity Information [Line Items]

Title of 12(b) Security

3.900% Senior Notes due 2030

Trading Symbol

AMT 30D

Security Exchange Name

NYSE

NEW YORK STOCK EXCHANGE, INC. | 4.100% Senior Notes due 2034

Entity Information [Line Items]

Title of 12(b) Security

4.100% Senior Notes due 2034

Trading Symbol

AMT 34A

Security Exchange Name

NYSE

NEW YORK STOCK EXCHANGE, INC. | 3.625% Senior Notes Due 2032

Entity Information [Line Items]

Title of 12(b) Security

3.625% Senior Notes due 2032

Trading Symbol

AMT 32B

Security Exchange Name

NYSE

NEW YORK STOCK EXCHANGE, INC. | 4.000 Senior Notes due 2033

Entity Information [Line Items]

Title of 12(b) Security

4.000% Senior Notes due 2033

Trading Symbol

AMT 33D

Security Exchange Name

NYSE

- Definition

Boolean flag that is true when the XBRL content amends previously-filed or accepted submission.

+ References

No definition available.

+ Details

Name:

dei_AmendmentFlag

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

Period Type:

duration

- Definition

Area code of city

+ References

No definition available.

+ Details

Name:

dei_CityAreaCode

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

Period Type:

duration

- Definition

For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period. The format of the date is YYYY-MM-DD.

+ References

No definition available.

+ Details

Name:

dei_DocumentPeriodEndDate

Namespace Prefix:

dei_

Data Type:

xbrli:dateItemType

Balance Type:

Period Type:

duration

- Definition

The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.

+ References

No definition available.

+ Details

Name:

dei_DocumentType

Namespace Prefix:

dei_

Data Type:

dei:submissionTypeItemType

Balance Type:

Period Type:

duration

- Definition

Address Line 1 such as Attn, Building Name, Street Name

+ References

No definition available.

+ Details

Name:

dei_EntityAddressAddressLine1

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

Period Type:

duration

- Definition

Name of the City or Town

+ References

No definition available.

+ Details

Name:

dei_EntityAddressCityOrTown

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

Period Type:

duration

- Definition

Code for the postal or zip code

+ References

No definition available.

+ Details

Name:

dei_EntityAddressPostalZipCode

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

Period Type:

duration

- Definition

Name of the state or province.

+ References

No definition available.

+ Details

Name:

dei_EntityAddressStateOrProvince

Namespace Prefix:

dei_

Data Type:

dei:stateOrProvinceItemType

Balance Type:

Period Type:

duration

- Definition

A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b-2

+ Details

Name:

dei_EntityCentralIndexKey

Namespace Prefix:

dei_

Data Type:

dei:centralIndexKeyItemType

Balance Type:

Period Type:

duration

- Definition

Indicate if registrant meets the emerging growth company criteria.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b-2

+ Details

Name:

dei_EntityEmergingGrowthCompany

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

Period Type:

duration

- Definition

Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.

+ References

No definition available.

+ Details

Name:

dei_EntityFileNumber

Namespace Prefix:

dei_

Data Type:

dei:fileNumberItemType

Balance Type:

Period Type:

duration

- Definition

Two-character EDGAR code representing the state or country of incorporation.

+ References

No definition available.

+ Details

Name:

dei_EntityIncorporationStateCountryCode

Namespace Prefix:

dei_

Data Type:

dei:edgarStateCountryItemType

Balance Type:

Period Type:

duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:

dei_EntityInformationLineItems

Namespace Prefix:

dei_

Data Type:

xbrli:stringItemType

Balance Type:

Period Type:

duration

- Definition

The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b-2

+ Details

Name:

dei_EntityRegistrantName

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

Period Type:

duration

- Definition

The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b-2

+ Details

Name:

dei_EntityTaxIdentificationNumber

Namespace Prefix:

dei_

Data Type:

dei:employerIdItemType

Balance Type:

Period Type:

duration

- Definition

Local phone number for entity.

+ References

No definition available.

+ Details

Name:

dei_LocalPhoneNumber

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

Period Type:

duration

- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 13e

-Subsection 4c

+ Details

Name:

dei_PreCommencementIssuerTenderOffer

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

Period Type:

duration

- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 14d

-Subsection 2b

+ Details

Name:

dei_PreCommencementTenderOffer

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

Period Type:

duration

- Definition

Title of a 12(b) registered security.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b

+ Details

Name:

dei_Security12bTitle

Namespace Prefix:

dei_

Data Type:

dei:securityTitleItemType

Balance Type:

Period Type:

duration

- Definition

Name of the Exchange on which a security is registered.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection d1-1

+ Details

Name:

dei_SecurityExchangeName

Namespace Prefix:

dei_

Data Type:

dei:edgarExchangeCodeItemType

Balance Type:

Period Type:

duration

- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as soliciting material pursuant to Rule 14a-12 under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 14a

-Subsection 12

+ Details

Name:

dei_SolicitingMaterial

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

Period Type:

duration

- Definition

Trading symbol of an instrument as listed on an exchange.

+ References

No definition available.

+ Details

Name:

dei_TradingSymbol

Namespace Prefix:

dei_

Data Type:

dei:tradingSymbolItemType

Balance Type:

Period Type:

duration

- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as written communications pursuant to Rule 425 under the Securities Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Securities Act

-Number 230

-Section 425

+ Details

Name:

dei_WrittenCommunications

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

Period Type:

duration

- Details

Name:

dei_EntityListingsExchangeAxis=exch_XNYS

Namespace Prefix:

Data Type:

Balance Type:

Period Type:

- Details

Name:

us-gaap_StatementClassOfStockAxis=us-gaap_CommonStockMember

Namespace Prefix:

Data Type:

Balance Type:

Period Type:

- Details

Name:

us-gaap_StatementClassOfStockAxis=amt_A0450SeniorNotesDue2027Member

Namespace Prefix:

Data Type:

Balance Type:

Period Type:

- Details

Name:

us-gaap_StatementClassOfStockAxis=amt_A0500SeniorNotesDue2028Member

Namespace Prefix:

Data Type:

Balance Type:

Period Type:

- Details

Name:

us-gaap_StatementClassOfStockAxis=amt_A1.000SeniorNotesDue2032Member

Namespace Prefix:

Data Type:

Balance Type:

Period Type:

- Details

Name:

us-gaap_StatementClassOfStockAxis=amt_A0875SeniorNotesDue2029Member

Namespace Prefix:

Data Type:

Balance Type:

Period Type:

- Details

Name:

us-gaap_StatementClassOfStockAxis=amt_A1250SeniorNotesDue2033Member

Namespace Prefix:

Data Type:

Balance Type:

Period Type:

- Details

Name:

us-gaap_StatementClassOfStockAxis=amt_A0400SeniorNotesDue2027Member

Namespace Prefix:

Data Type:

Balance Type:

Period Type:

- Details

Name:

us-gaap_StatementClassOfStockAxis=amt_A0950SeniorNotesDue2030Member

Namespace Prefix:

Data Type:

Balance Type:

Period Type:

- Details

Name:

us-gaap_StatementClassOfStockAxis=amt_A4125SeniorNotesDue2027Member

Namespace Prefix:

Data Type:

Balance Type:

Period Type:

- Details

Name:

us-gaap_StatementClassOfStockAxis=amt_A4625SeniorNotesDue2031Member

Namespace Prefix:

Data Type:

Balance Type:

Period Type:

- Details

Name:

us-gaap_StatementClassOfStockAxis=amt_A3.900SeniorNotesDue2030Member

Namespace Prefix:

Data Type:

Balance Type:

Period Type:

- Details

Name:

us-gaap_StatementClassOfStockAxis=amt_A4.100SeniorNotesDue2034Member

Namespace Prefix:

Data Type:

Balance Type:

Period Type:

- Details

Name:

us-gaap_StatementClassOfStockAxis=amt_A3.625SeniorNotesDue2032Member

Namespace Prefix:

Data Type:

Balance Type:

Period Type:

- Details

Name:

us-gaap_StatementClassOfStockAxis=amt_A4.000SeniorNotesDue2033Member

Namespace Prefix:

Data Type:

Balance Type:

Period Type: