Unused letters of credit.

No definition available.

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Namespace Prefix:	alit_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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- Definition

Face (par) amount of debt instrument at time of issuance.

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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

Amount of the required periodic payments applied to principal.

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

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- Definition

Amount of increase (decrease) of the credit facility.

+ References

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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 the required periodic payments of both interest and principal.

+ References

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- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Debt - Additional Information (Details) - USD ($)	1 Months Ended			3 Months Ended
Debt - Additional Information (Details) - USD ($)	Jan. 31, 2025	Dec. 31, 2024	Mar. 31, 2023	Mar. 31, 2026	Mar. 31, 2025	May 31, 2025	Aug. 31, 2021
Debt Instrument [Line Items]
Interest expense related to debt instruments				$ 28,000,000	$ 32,000,000
$330 million Revolving Credit Facility, Amended
Debt Instrument [Line Items]
Line of credit, maximum borrowing capacity				330,000,000		$ 330,000,000	$ 294,000,000
Unused letters of credit				0
Revolving credit facility, borrowings				0
Periodic payment				0	0
Revolving Credit Facility
Debt Instrument [Line Items]
Increase in revolving credit facility			$ 300,000,000
Seventh Incremental Term Loans
Debt Instrument [Line Items]
Face amount	$ 2,030,000,000
Seventh Incremental Term Loans \| Alight Holdings
Debt Instrument [Line Items]
Debt instrument, variable interest rate	1.75%	2.25%
Term Loan, Amended
Debt Instrument [Line Items]
Principal payment				$ 5,000,000	$ 5,000,000