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Securities - Additional Information (Detail) - USD ($)	3 Months Ended
Securities - Additional Information (Detail) - USD ($)	Mar. 31, 2022	Jun. 30, 2021	Jun. 30, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Securities available-for-sale, allowance for credit losses			$ 2,000,000	$ 1,000,000
Securities held-to-maturity, allowance for credit losses			0	1,000,000
Securities held-to-maturity, nonaccrual			0	0
Equity securities without readily determinable fair values, impairment loss adjustment	$ 3,000,000	$ 3,000,000
Financial Asset, Past Due
Debt Securities, Available-for-sale [Line Items]
Securities held-to-maturity, past due			0	0
Other assets
Debt Securities, Available-for-sale [Line Items]
Federal Home Loan Bank stock			107,000,000	110,000,000
Federal Reserve Bank stock			$ 528,000,000	$ 558,000,000