Assets Purchased under Resale Agreements and Sold under Repurchase Agreements - Repurchase Agreements (Details) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Amount of securities sold under repurchase agreements
Gross repurchase agreements		$ 0	$ 300,000,000
Extinguishment of repurchase agreements	$ 300,000,000
Repurchase agreements’ extinguishment cost		$ 4,000,000	$ 0	$ 0
Securities sold under agreements to repurchase average rate paid			3.07%	2.61%