v3.25.3

Share-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended		9 Months Ended
	Dec. 31, 2022	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
2021 Omnibus Incentive Plan
Class Of Stock [Line Items]
Remaining shares of common stock authorized		89,384,120		89,384,120
Time Based Restricted Stock Units \| 2021 Omnibus Incentive Plan
Class Of Stock [Line Items]
Percentage of units granted subject to vesting requirements				58.00%
Performance-based RSUs
Class Of Stock [Line Items]
Granted (in dollars per share)				$ 6.09	$ 8.97
Total future compensation expense		$ 5.0		$ 5.0
Remaining weighted-average amortization period				1 year 7 months 6 days
Performance-based RSUs \| 2021 Omnibus Incentive Plan
Class Of Stock [Line Items]
Percentage of units granted subject to vesting requirements				42.00%
RSUs and PRSUs
Class Of Stock [Line Items]
Vesting period				3 years
Stock Based Compensation		3.0	$ 11.0	$ 14.0	$ 59.0
RSUs
Class Of Stock [Line Items]
Granted (in dollars per share)				$ 5.76	$ 8.83
Total future compensation expense		$ 41.0		$ 41.0
Remaining weighted-average amortization period				1 year 11 months 15 days
Employee Stock \| Employee Stock Purchase Plan
Class Of Stock [Line Items]
Remaining shares available for grant		12,792,789		12,792,789
Number of shares issued				3,481,139
Stock Based Compensation		$ 0.3	$ 0.3	$ 0.8	$ 1.2
Employee Stock \| Employee Stock Purchase Plan \| Class A Common Stock
Class Of Stock [Line Items]
Stock plan payment period	6 months
Maximum number of shares, an employee can purchase (in shares)	1,250
Purchase price of common stock, percent of fair market value	85.00%
Employee Stock \| Employee Stock Purchase Plan \| Class A Common Stock \| Minimum
Class Of Stock [Line Items]
Percentage of payroll deductions	1.00%
Employee Stock \| Employee Stock Purchase Plan \| Class A Common Stock \| Maximum
Class Of Stock [Line Items]
Percentage of payroll deductions	10.00%

Percentage of units granted subject to vesting requirements.

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The highest quantity of shares an employee can purchase under the plan per period.

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Purchase price of common stock expressed as a percentage of its fair value.

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Alight, Inc. / Delaware 10-Q