Gains and Losses Included in Net (Income) from Liabilities Measured at Fair Value (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total realized and unrealized (gains) losses included in net (income), liabilities	$ 9	$ 8	$ (48)	$ (111)
Total (gains) losses included in net (income) attributable to liabilities still held, liabilities	12	7	(41)	(106)
Net Investment Income
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total realized and unrealized (gains) losses included in net (income), liabilities	0	0	0	0
Total (gains) losses included in net (income) attributable to liabilities still held, liabilities	0	0	0	0
Net investment (gains) losses
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total realized and unrealized (gains) losses included in net (income), liabilities	9	8	(48)	(111)
Total (gains) losses included in net (income) attributable to liabilities still held, liabilities	$ 12	$ 7	$ (41)	$ (106)