Regulatory Capital - Additional Information (Detail) $ in Billions	6 Months Ended
	Dec. 31, 2022 USD ($)	Mar. 31, 2020
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Capital conservation buffer risk-weighted assets	2.50%
Maximum asset value required to be maintained leverage ratio	$ 10
Maximum [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Leverage ratio		0.09