Derivative Financial Instruments (Offsetting Liabilities) (Detail) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Derivative [Line Items]
Gross Liabilities Presented in the Consolidated Balance Sheet	$ 19	$ 27
Gross amounts not offset in the consolidated balance sheet, financial instruments	0	0
Gross amounts not offset in the consolidated balance sheet, cash collateral paid	11	17
Gross amounts not offset in the consolidated balance sheet, net amounts	8	10
Interest Rate Contract [Member] \| Over The Counter [Member]
Derivative [Line Items]
Gross Liabilities Presented in the Consolidated Balance Sheet	19	27
Gross amounts not offset in the consolidated balance sheet, financial instruments	0	0
Gross amounts not offset in the consolidated balance sheet, cash collateral paid	11	17
Gross amounts not offset in the consolidated balance sheet, net amounts	$ 8	$ 10

Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

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