Allowance for Credit Losses on Loans and Leases - Summary of Activity in Allowance for Loan and Lease Losses (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Valuation Allowance [Line Items]
Balance, beginning of period	$ 199	$ 194
Adjustment for Purchased PCD Loans	51
Charge-offs	(7)	(13)
Recoveries	11	15
Provision for (recovery of) credit losses on loans and leases	139	3
Balance, end of period	393	199
Mortgage Receivable
Valuation Allowance [Line Items]
Balance, beginning of period	178	176
Adjustment for Purchased PCD Loans	21
Charge-offs	(5)	(6)
Recoveries	4	2
Provision for (recovery of) credit losses on loans and leases	92	6
Balance, end of period	290	178
Other Loans
Valuation Allowance [Line Items]
Balance, beginning of period	21	18
Adjustment for Purchased PCD Loans	30
Charge-offs	(2)	(7)
Recoveries	7	13
Provision for (recovery of) credit losses on loans and leases	47	(3)
Balance, end of period	$ 103	$ 21