The floor rate of debt instrument.

No definition available.

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Namespace Prefix:	acm_
Data Type:	dtr-types:percentItemType
Balance Type:	na
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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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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

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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- Definition

Indebtedness divided by net capital.

+ References

No definition available.

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Debt - Credit Agreement (Details)	Mar. 10, 2026 USD ($)	Jun. 30, 2026 USD ($)	Jun. 10, 2026 USD ($)	Sep. 30, 2025 USD ($)	Apr. 19, 2024
Debt
Outstanding standby letters of credit		$ 0
The Term Loan A Facility \| Term Loan Facility
Debt
Maximum borrowing capacity	$ 950,000,000
Term Loan B Facility \| Term Loan Facility
Debt
Maximum borrowing capacity	$ 500,000,000
Term Loan B Facility \| SOFR
Debt
Debt instrument, floor rate (as percent)	0.00%
Interest rate, basis spread (as percent)	1.50%
Term Loan B Facility \| Base Rate
Debt
Debt instrument, floor rate (as percent)	0.00%
Interest rate, basis spread (as percent)	0.50%
Amended Credit Agreement \| Maximum
Debt
Consolidated leverage ratio					4.00
Revolving Credit Facility \| USD \| SOFR
Debt
Debt instrument, floor rate (as percent)	0.00%
Revolving Credit Facility \| USD \| SOFR \| Minimum
Debt
Interest rate, basis spread (as percent)	1.125%
Revolving Credit Facility \| USD \| SOFR \| Maximum
Debt
Interest rate, basis spread (as percent)	2.00%
Revolving Credit Facility \| USD \| Base Rate
Debt
Debt instrument, floor rate (as percent)	0.00%
Revolving Credit Facility \| USD \| Base Rate \| Minimum
Debt
Interest rate, basis spread (as percent)	0.125%
Revolving Credit Facility \| USD \| Base Rate \| Maximum
Debt
Interest rate, basis spread (as percent)	1.00%
Revolving Credit Facility \| The 1.5 Billion Revolving Credit Facility
Debt
Maximum borrowing capacity	$ 1,500,000,000	1,500,000,000	$ 1,500,000,000	$ 1,500,000,000
Outstanding standby letters of credit		1,500,000,000		1,500,000,000
Current borrowing capacity		1,495,600,000		1,495,600,000
Revolving Credit Facility \| The 1.5 Billion Revolving Credit Facility \| USD
Debt
Maximum borrowing capacity	$ 1,500,000,000
Revolving Credit Facility \| Amended Credit Agreement
Debt
Outstanding standby letters of credit		4,400,000		$ 4,400,000
Revolving Credit Facility \| Amended Credit Agreement \| Minimum
Debt
Commitment fee on the unused portion of leverage ratio	0.15%
Revolving Credit Facility \| Amended Credit Agreement \| Maximum
Debt
Commitment fee on the unused portion of leverage ratio	0.30%
Revolving Credit Facility \| The 500 Million Revolving Credit Facility
Debt
Maximum borrowing capacity		500,000,000	$ 500,000,000
Current borrowing capacity		$ 500,000,000