Short and Long-Term Funding, FHLB Advances (Components of Short-term and Long-term Funding) (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Short-term Funding [Abstract]
Federal funds purchased	$ 505	$ 120
Securities sold under agreements to repurchase	276,169	319,412
Federal funds purchased and securities sold under agreements to repurchase	276,674	319,532
Commercial paper	7,687	34,730
Total short-term funding	284,361	354,262
Long-Term Funding
Subordinated Debt	250,000	250,000
Other Long-term Debt and Capitalized Costs	(617)	(839)
Finance lease liability	490	163
Long-term Debt	249,484	249,324
TotalShortTermLongTermExcludingFHLB	533,844	603,587
Advance from Federal Home Loan Bank	2,583,000	0
Advance from Federal Home Loan Bank [Abstract]
Advance from Federal Home Loan Bank	2,583,000	0
Long-Term Federal Home Loan Bank Advances	1,208,791	1,621,047
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Amount of Advances	3,777,478	1,621,047
Debt, Long-Term and Short-Term, Combined Amount	4,311,322	2,224,633
Fair Value Hedging [Member]
Long-Term Funding
Subordinated Debt	(389)	0
Advance from Federal Home Loan Bank	(14,314)	0
Advance from Federal Home Loan Bank [Abstract]
Advance from Federal Home Loan Bank	$ (14,314)	$ 0

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Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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