Earnings Per Share - Summary of Basic and Diluted Earnings Per Share (Details) $ / shares in Units, $ in Millions	3 Months Ended
Mar. 31, 2022 USD ($) $ / shares shares
Numerator
Net loss attributable to Alight, Inc. - basic and diluted \| $	$ (11)
Denominator
Weighted average shares outstanding - basic and diluted \| shares	456,838,216
Basic and diluted net loss per share \| $ / shares	$ (0.02)

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details