Netting Arrangements for Certain Financial Instruments and Securities Financing Activities - Information on Company's Accounting Netting Adjustments and Items Not Offset in Consolidated Balance Sheet Assets But Available for Offset in Event of Default (Parenthetical) (Detail) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Offsetting [Abstract]
Cash collateral netted against derivative assets	$ 1,100	$ 528
Derivative assets not subject to netting arrangements	$ 21	$ 57

Netting Arrangements for Certain Financial Instruments and Securities Financing Activities - Information on Company's Accounting Netting Adjustments and Items Not Offset in Consolidated Balance Sheet Assets But Available for Offset in Event of Default (Parenthetical) (Detail) - USD ($)
$ in Millions

Mar. 31, 2022

Dec. 31, 2021

Cash collateral netted against derivative assets

$ 1,100

$ 528

Derivative assets not subject to netting arrangements

$ 21

$ 57