Derivatives and Hedge Accounting Activities (Schedule of Amounts Recorded on Consolidated Balance Sheet Related to Cumulative Basis Adjustments for Fair Value Hedges) (Detail) - Designated as Hedging Instrument - Fair Value Hedging - Long-term Debt - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Carrying Amount of the Hedged Asset (Liability)	$ (351)	$ (352)
Cumulative Amount of Fair Value Hedging Adjustments Included in the Carrying Amount of the Hedged Assets (Liabilities)	$ (1)	$ (2)