Variable Interest Entities and Asset Securitizations - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 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		$ 22,000,000
Total assets of partnerships in which the company invested	207,671,729,000		207,671,729,000		200,729,841,000
Investment in partnership carrying amount	1,500,000,000		1,500,000,000		1,500,000,000
Unfunded commitments includes carrrying amount of its investments	522,000,000		522,000,000		545,000,000
Contingent Commitments to Provide Additional Capital Contributions to Partnerships	52,000,000		52,000,000
Maximum exposure to loss of investments in real estate partnerships	2,100,000,000		2,100,000,000
Investments amortized to income tax expense	42,000,000	$ 36,000,000	82,000,000	$ 57,000,000
Federal tax credits and other federal tax benefits recognized	49,000,000	$ 42,000,000	95,000,000	$ 65,000,000
Variable Interest Entity Primary Beneficiary [Member]
Total assets of partnerships in which the company invested	$ 9,700,000,000		$ 9,700,000,000		$ 9,200,000,000