XML 99 R89.htm IDEA: XBRL DOCUMENT
v3.25.3

ACQUISITIONS - Allocation of Purchase Price for Asset Acquisitions (Details) - Acquisitions 2025 $ in Millions | 9 Months Ended
--- | ---
Sep. 30, 2025 USD ($)
Asset Acquisition [Line Items] |
Current assets | $ 6.3
Property and equipment | 237.0
Other non-current assets | 31.8
Current liabilities | (1.3)
Other non-current liabilities | (24.8)
Net assets acquired | 364.6
Purchase price | 364.6
Tenant-related intangible assets |
Asset Acquisition [Line Items] |
Intangible assets | 61.1
Network location intangible assets |
Asset Acquisition [Line Items] |
Intangible assets | 48.1
Other intangible assets |
Asset Acquisition [Line Items] |
Intangible assets | $ 6.4

X
- Definition Asset Acquisition, Assets Acquired and Liabilities Assumed, Net + References No definition available. + Details
Name: | amt_AssetAcquisitionAssetsAcquiredandLiabilitiesAssumedNet
Namespace Prefix: | amt_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Asset Acquisition, Assets, Current + References No definition available. + Details
Name: | amt_AssetAcquisitionAssetsCurrent
Namespace Prefix: | amt_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Asset Acquisition, Finite-Lived Intangible Assets, Net + References No definition available. + Details
Name: | amt_AssetAcquisitionFiniteLivedIntangibleAssetsNet
Namespace Prefix: | amt_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Asset Acquisition, Liabilities, Current + References No definition available. + Details
Name: | amt_AssetAcquisitionLiabilitiesCurrent
Namespace Prefix: | amt_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Asset Acquisition, Other Assets, Non Current + References No definition available. + Details
Name: | amt_AssetAcquisitionOtherAssetsNonCurrent
Namespace Prefix: | amt_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Asset Acquisition, Other Liabilities, Noncurrent + References No definition available. + Details
Name: | amt_AssetAcquisitionOtherLiabilitiesNoncurrent
Namespace Prefix: | amt_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Asset Acquisition, Property Plant And Equipment, Net + References No definition available. + Details
Name: | amt_AssetAcquisitionPropertyPlantAndEquipmentNet
Namespace Prefix: | amt_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of consideration transferred in asset acquisition. Includes, but is not limited to, cash, liability incurred by acquirer, and equity interest issued by acquirer. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 805 -SubTopic 50 -Name Accounting Standards Codification -Section 55 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479908/805-50-55-1 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 805 -SubTopic 50 -Name Accounting Standards Codification -Section 25 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480060/805-50-25-1 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 805 -SubTopic 50 -Name Accounting Standards Codification -Section 30 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480027/805-50-30-1 Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 805 -SubTopic 50 -Name Accounting Standards Codification -Section 30 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480027/805-50-30-2 + Details
Name: | us-gaap_AssetAcquisitionConsiderationTransferred
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- 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 Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 350 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482573/350-20-50-4 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 805 -SubTopic 50 -Name Accounting Standards Codification -Section 15 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480123/805-50-15-3 + Details
Name: | us-gaap_AssetAcquisitionLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_AssetAcquisitionAxis=amt_A2025AssetAcquisitionsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_CustomerRelationshipsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=amt_AcquiredNetworkLocationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=amt_AcquiredOtherIntangibleAssetsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |