Fair Value Of Financial Instruments (Gains And Losses On Fair Value Option Included In The Company's Consolidated Statements Of Operations) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Accounts Notes And Loans Receivable [Line Items]
Net gains (losses) on financial instruments at fair value and foreign exchange	$ 45	$ 40	$ (80)
Non Variable Interest Entity [Member]
Accounts Notes And Loans Receivable [Line Items]
Net gains (losses) on financial instruments at fair value and foreign exchange	45	40	(80)
Variable Interest Entity [Member]
Accounts Notes And Loans Receivable [Line Items]
Net gains (losses) on financial instruments at fair value and foreign exchange	(14)	(8)	108
Investments Carried At Fair Value [Member]
Accounts Notes And Loans Receivable [Line Items]
Net gains (losses) on financial instruments at fair value and foreign exchange	(17)	3	2
Fixed Maturity Securities Held At Fair Value - VIE [Member] | Variable Interest Entity [Member]
Accounts Notes And Loans Receivable [Line Items]
Net gains (losses) on financial instruments at fair value and foreign exchange	(5)	4	4
Loans Receivable and Other Instruments at Fair Value [Member] | Variable Interest Entity [Member] | Residential Mortgage Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Net gains (losses) on financial instruments at fair value and foreign exchange	10	32	0
Loan Repurchase Commitments [Member] | Variable Interest Entity [Member]
Accounts Notes And Loans Receivable [Line Items]
Net gains (losses) on financial instruments at fair value and foreign exchange	0	(4)	118
Other Assets [Member] | Variable Interest Entity [Member]
Accounts Notes And Loans Receivable [Line Items]
Net gains (losses) on financial instruments at fair value and foreign exchange	9	0	(4)
Medium Term Notes [Member] | Non Variable Interest Entity [Member]
Accounts Notes And Loans Receivable [Line Items]
Net gains (losses) on financial instruments at fair value and foreign exchange	24	17	(15)
Variable Interest Entity Notes [Member] | Variable Interest Entity [Member]
Accounts Notes And Loans Receivable [Line Items]
Net gains (losses) on financial instruments at fair value and foreign exchange	$ (20)	$ (50)	$ (12)