v3.26.1
Document and Entity Information
May 27, 2026
Document And Entity Information [Line Items]  
Entity Registrant Name AMERICAN TOWER CORP /MA/
Amendment Flag false
Entity Central Index Key 0001053507
Document Type 8-K
Document Period End Date May 27, 2026
Entity Incorporation State Country Code DE
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 MA
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
Common Stock [Member]  
Document And Entity Information [Line Items]  
Security 12b Title Common Stock, $0.01 par value
Trading Symbol AMT
Security Exchange Name NYSE
A 0450 Senior Notes Due 2027 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title 0.450% Senior Notes due 2027
Trading Symbol AMT 27C
Security Exchange Name NYSE
A 0400 Senior Notes Due 2027 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title 0.400% Senior Notes due 2027
Trading Symbol AMT 27D
Security Exchange Name NYSE
A 4125 Senior Notes Due 2027 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title 4.125% Senior Notes due 2027
Trading Symbol AMT 27F
Security Exchange Name NYSE
A 0500 Senior Notes Due 2028 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title 0.500% Senior Notes due 2028
Trading Symbol AMT 28A
Security Exchange Name NYSE
A 0875 Senior Notes Due 2029 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title 0.875% Senior Notes due 2029
Trading Symbol AMT 29B
Security Exchange Name NYSE
A 0950 Senior Notes Due 2030 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title 0.950% Senior Notes due 2030
Trading Symbol AMT 30C
Security Exchange Name NYSE
A 3.900 Senior Notes Due 2030 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title 3.900% Senior Notes due 2030
Trading Symbol AMT 30D
Security Exchange Name NYSE
A 4625 Senior Notes Due 2031 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title 4.625% Senior Notes due 2031
Trading Symbol AMT 31B
Security Exchange Name NYSE
A 1.000 Senior Notes Due 2032 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title 1.000% Senior Notes due 2032
Trading Symbol AMT 32
Security Exchange Name NYSE
A 3.625 Senior Notes Due 2032 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title 3.625% Senior Notes due 2032
Trading Symbol AMT 32B
Security Exchange Name NYSE
A 1250 Senior Notes Due 2033 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title 1.250% Senior Notes due 2033
Trading Symbol AMT 33
Security Exchange Name NYSE
A 4.100 Senior Notes Due 2034 [Member]  
Document And Entity Information [Line Items]  
Security 12b Title 4.100% Senior Notes due 2034
Trading Symbol AMT 34A
Security Exchange Name NYSE