Fair Value Measurements - Activity for Level 3 Assets Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Level 3 CMO [Roll Forward]
Other Borrowings, Fair Value Disclosure	$ 123,065		$ 123,065		$ 132,030
Total included in earnings			0	$ (1,105)
Proceeds from (Repayments of) Debt			4,598,891	1,592,000
Unrealized net holding gains (losses) on securities available-for-sale arising during the period	(64,145)	$ (72,572)	3,826	$ (682,398)
Credit-Link Notes
Level 3 CMO [Roll Forward]
Other Borrowings, Fair Value Disclosure	123,065		123,065		$ 132,030
Level 3
Level 3 CMO [Roll Forward]
Equity warrants, Balance, beginning of period			4,048
Total included in earnings			(457)
Total included in other comprehensive income			0
Payments for Repurchase of Warrants			0
Sales, Equity Warrants			390
Fair Value, Assets, Level 2 to Level 1 Transfers, Amount			0
Warrant (loss) income			62
Fair Value, Equity, Transfers to Level 1, Amount			36
Level 3 | Credit-Link Notes
Level 3 CMO [Roll Forward]
Total included in earnings			(1,526)
Total included in other comprehensive income			(4,057)
Proceeds from Issuance of Debt			0
Proceeds from (Repayments of) Debt			(3,382)
Fair Value, Equity, Level 2 to Level 1 Transfers, Description
Debt Securities Exercises and Settlements			0
Fair Value, Equity, Transfers to Level 1, Amount			0
Level 3 | Corporate Debt Securities
Level 3 CMO [Roll Forward]
Total included in earnings			0
Proceeds from Issuance of Debt			0
Proceeds from (Repayments of) Debt			0
Fair Value, Equity, Level 2 to Level 1 Transfers, Description			8,750
Debt Securities Exercises and Settlements			0
Fair Value, Measurements, Recurring
Level 3 CMO [Roll Forward]
Equity warrants, Balance, beginning of period			4,048
Equity warrants, Balance, end of period	3,883		3,883
Fair Value, Measurements, Recurring | Level 3
Level 3 CMO [Roll Forward]
Equity warrants, Balance, beginning of period			4,048
Equity warrants, Balance, end of period	3,883		3,883
Fair Value, Measurements, Recurring | Level 3 | Corporate Debt Securities
Level 3 CMO [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	$ 6,990		6,990
Total included in other comprehensive income			(1,760)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value			0
Asset-backed | Fair Value, Measurements, Recurring | Level 3
Level 3 CMO [Roll Forward]
Unrealized net holding gains (losses) on securities available-for-sale arising during the period			$ (1,760)