Assets Purchased under Resale Agreements and Sold under Repurchase Agreements - Resale Agreements (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Offsetting Assets [Line Items]
Gross resale agreements	$ 785,000,000	$ 760,000,000
Average yield	2.87%	2.12%	1.53%
Loans purchased under agreements to resell	$ 0	$ 32,000,000
Loans Purchased Under Resale Agreements
Offsetting Assets [Line Items]
Weighted average yield (as a percent)		2.16%	1.53%