Gains and Losses Included in Net (Income) from Liabilities Measured at Fair Value (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total realized and unrealized (gains) losses included in net (income), liabilities	$ (125)	$ 66	$ 47
Total (gains) losses included in net (income) attributable to liabilities still held, liabilities	(119)	72	52
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
Total (gains) losses included in net (income) attributable to liabilities still held, liabilities	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	(125)	66	47
Total (gains) losses included in net (income) attributable to liabilities still held, liabilities	$ (119)	$ 72	$ 52