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Disposal group including discontinued operation contingent consideration amount.

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Date when the acquirer obtains control of the acquiree, in YYYY-MM-DD format.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount classified as cash and cash equivalents attributable to disposal group held for sale or disposed of.

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Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

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Amount classified as liabilities attributable to disposal group held for sale or disposed of.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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Basis of Presentation and Nature of Business - Additional Information (Details) - USD ($) $ in Millions	Mar. 20, 2024	Jul. 02, 2021	Mar. 31, 2024
Alight Holdings \| Maximum
Basis Of Presentation And Nature Of Business [Line Items]
Non-voting ownership percentage held by noncontrolling interest			1.00%
Special Purpose Acquisition Company
Basis Of Presentation And Nature Of Business [Line Items]
Business combination, closing date of acquisition		Jul. 02, 2021
Alight \| Special Purpose Acquisition Company \| Alight Holdings
Basis Of Presentation And Nature Of Business [Line Items]
Percentage of economic interest			99.00%
Business combination, percentage of voting power			100.00%
Alight \| Professional Service Segment And Payroll And HCM Outsourcisg Business
Basis Of Presentation And Nature Of Business [Line Items]
Cash and cash equivalents	$ 1,000
Contingent consideration amount	150
Consideration for disposal of assets and liabilities	1,200
Alight \| Professional Service Segment And Payroll And HCM Outsourcisg Business \| seller note
Basis Of Presentation And Nature Of Business [Line Items]
purchase price by seller	$ 200