Debt Instrument, Repaid, Including Interest

No definition available.

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Namespace Prefix:	amt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Debt Instrument, Repaid, Principal Amount

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- 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.

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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- Definition

Reflects the difference between the fair value of payments made to legally extinguish a debt and its carrying value at that time. This item excludes the write-off of amounts previously capitalized as debt issuance costs.

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Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References

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LONG-TERM OBLIGATIONS - Repayments of Senior Notes (Details) € in Millions, $ in Millions							3 Months Ended		9 Months Ended
	Sep. 14, 2026 USD ($)	Jun. 18, 2026 USD ($)	Jun. 18, 2026 EUR (€)	May 21, 2026 USD ($)	Apr. 14, 2026 USD ($)	Feb. 13, 2026 USD ($)	Sep. 30, 2026 USD ($)	Sep. 30, 2025 USD ($)	Sep. 30, 2026 USD ($)	Sep. 30, 2025 USD ($)	Jun. 17, 2026 USD ($)	Jun. 17, 2026 EUR (€)	Dec. 31, 2025 USD ($)
Debt Instrument [Line Items]
Accrued and unpaid interest							$ 261.7		$ 261.7				$ 425.2
Loss on retirement of long-term obligations							0.0	$ 0.0	3.2	$ 0.0
American Tower Corporation
Debt Instrument [Line Items]
Debt outstanding							35,768.3		35,768.3				$ 35,409.2
American Tower Corporation \| Senior notes \| 4.400% senior notes
Debt Instrument [Line Items]
Stated interest rate (as a percent)						4.40%							4.40%
Aggregate principal amount repaid						$ 500.0
Debt outstanding							0.0		0.0				$ 499.9
American Tower Corporation \| Senior notes \| 1.600% senior notes
Debt Instrument [Line Items]
Stated interest rate (as a percent)					1.60%								1.60%
Aggregate principal amount repaid					$ 700.0
Debt outstanding					$ 0.0		0.0		0.0				$ 699.7
American Tower Corporation \| Senior notes \| 1.950% senior notes
Debt Instrument [Line Items]
Stated interest rate (as a percent)				1.95%									1.95%
Aggregate principal amount repaid				$ 500.0
Debt outstanding				$ 0.0			$ 0.0		$ 0.0				$ 586.9
American Tower Corporation \| Senior notes \| 4.125% senior notes
Debt Instrument [Line Items]
Stated interest rate (as a percent)			4.125%				4.125%		4.125%
Aggregate principal amount repaid \| €			€ 250.0
Debt outstanding							$ 396.1		$ 396.1				$ 703.1
Redemption price percentage		100.969%	100.969%
Debt instrument, repurchase amount including interest		$ 290.2	€ 253.3
Accrued and unpaid interest											$ 1.0	€ 0.9
Loss on retirement of long-term obligations		3.2
Loss on retirement due to prepayment consideration		$ 2.8
Outstanding principal balance \| €			€ 350.0
American Tower Corporation \| Senior notes \| 1.450% senior notes
Debt Instrument [Line Items]
Stated interest rate (as a percent)	1.45%												1.45%
Aggregate principal amount repaid	$ 600.0
Debt outstanding	$ 0.0						$ 0.0		$ 0.0				$ 598.9
American Tower Corporation \| Senior notes \| 5.300% senior notes
Debt Instrument [Line Items]
Stated interest rate (as a percent)	5.30%						5.30%		5.30%
Debt outstanding							$ 494.7		$ 494.7				0.0
American Tower Corporation \| Senior notes \| 5.560% senior notes
Debt Instrument [Line Items]
Stated interest rate (as a percent)	5.56%						5.56%		5.56%
Debt outstanding							$ 494.9		$ 494.9				0.0
American Tower Corporation \| Senior notes \| 5.750% senior notes
Debt Instrument [Line Items]
Stated interest rate (as a percent)	5.75%						5.75%		5.75%
Debt outstanding							$ 592.0		$ 592.0				$ 0.0