Variable Interest Entities and Asset Securitizations - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Loss on securitization of assets	$ 0
Other assets for its "investment" in the common securities recognized by the company of various trusts	22,000,000		$ 22,000,000
Total assets of partnerships in which the company invested	202,956,407,000		200,729,841,000
Investment in partnership carrying amount	1,500,000,000		1,500,000,000
Unfunded commitments includes carrrying amount of its investments	547,000,000		545,000,000
Maximum exposure to loss of investments in real estate partnerships	2,000,000,000.0
Investments amortized to income tax expense	40,000,000	$ 20,000,000
Federal tax credits and other federal tax benefits recognized	46,000,000	$ 23,000,000
Variable Interest Entity Primary Beneficiary [Member]
Total assets of partnerships in which the company invested	$ 9,200,000,000		$ 9,200,000,000