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Other Borrowings - Short-Term Borrowings (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2021	Dec. 31, 2020
FHLB Advances
Outstanding advances	$ 0	$ 0	$ 0
Non- interest expense		$ (11,706)
Short term borrowings
FHLB Advances
Long-term Debt, Weighted Average Interest Rate, over Time		2.22%	0.63%
FHLB Advances
FHLB Advances
Loans pledged via a blanket lien to the FHLB for advances and letters of credit		$ 3,700
Investment securities pledged		227,600
Total borrowing capacity at FHLB		2,800,000
Letter of credit borrowed		12,000
Unused net credit available with the FHLB		2,800,000
Average amount of FHLB advances outstanding		2,000	$ 745,900
Payments of FHLB advances	700,000
FHLB Advances \| Interest rate swap
FHLB Advances
Non- interest expense	38,800
FRB Borrowings
FHLB Advances
Letter of credit borrowed	$ 0	0	$ 0
Maximum borrowing capacity		981,100
Loans secured by blanket lien		$ 1,600