Liability for Policy and Contract Claims - Additional Information (Detail) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021	Dec. 31, 2020
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred related to insured events of prior year	$ (483)	$ (332)
Liability for Claims and Claims Adjustment Expense	11,915	$ 11,546	$ 11,841	$ 11,486
Long-term Care Insurance
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred related to insured events of prior year	(483)
GNW Long Term Care Insurance [Member] | GNW Covid Nineteen [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred related to insured events of prior year	53
GNW Long Term Care Insurance [Member] | GNW Covid Nineteen [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Liability for Claims and Claims Adjustment Expense	156		$ 209
Enact | GNW Covid Nineteen [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred related to insured events of prior year	$ 146