Loans and Allowance for Credit Losses on Loans - Allowance For Credit-Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Allowance for credit losses
Balance, beginning of period	$ 44,014
Provision for credit losses	7,817	$ 1,981
Loans charged to the allowance		(931)	$ (1,257)
Recoveries of loans previously charged off	7	7	753
Balance, end of period	51,838	32,102	44,014
Allowance for loan losses
Balance, beginning of period		31,344	31,344
Provision for credit losses			13,473
ACL Loans
Provision for credit losses	6,867	2,451
Provision for credit losses, ACL Loans	7,817	1,981
Provision for credit losses, ACL-OBCE's	(900)	500
ASU 2016-13 \| Impact from adoption of ASU
Allowance for credit losses
Balance, beginning of period		(299)	(299)
Mortgage warehouse lines of credit
Allowance for credit losses
Balance, beginning of period	1,249
Provision for credit losses	415	(55)
Balance, end of period	1,664	1,941	1,249
Allowance for loan losses
Balance, beginning of period		1,955	1,955
Provision for credit losses			(747)
ACL Loans
Provision for credit losses, ACL Loans	415	(55)
Mortgage warehouse lines of credit \| ASU 2016-13 \| Impact from adoption of ASU
Allowance for credit losses
Balance, beginning of period		41	41
Residential real estate
Allowance for credit losses
Balance, beginning of period	7,029
Provision for credit losses	349	102
Loans charged to the allowance			(4)
Balance, end of period	7,378	4,547	7,029
Allowance for loan losses
Balance, beginning of period		4,170	4,170
Provision for credit losses			2,588
ACL Loans
Provision for credit losses, ACL Loans	349	102
Residential real estate \| ASU 2016-13 \| Impact from adoption of ASU
Allowance for credit losses
Balance, beginning of period		275	275
Multi-family financing
Allowance for credit losses
Balance, beginning of period	16,781
Provision for credit losses	3,070	527
Balance, end of period	19,851	15,131	16,781
Allowance for loan losses
Balance, beginning of period		14,084	14,084
Provision for credit losses			2,177
ACL Loans
Provision for credit losses, ACL Loans	3,070	527
Multi-family financing \| ASU 2016-13 \| Impact from adoption of ASU
Allowance for credit losses
Balance, beginning of period		520	520
Healthcare financing
Allowance for credit losses
Balance, beginning of period	9,882
Provision for credit losses	1,871	1,018
Balance, end of period	11,753	5,618	9,882
Allowance for loan losses
Balance, beginning of period		4,461	4,461
Provision for credit losses			5,282
ACL Loans
Provision for credit losses, ACL Loans	1,871	1,018
Healthcare financing \| ASU 2016-13 \| Impact from adoption of ASU
Allowance for credit losses
Balance, beginning of period		139	139
Commercial and commercial real estate
Allowance for credit losses
Balance, beginning of period	8,326
Provision for credit losses	2,149	431
Loans charged to the allowance		(931)	(1,238)
Recoveries of loans previously charged off	7		746
Balance, end of period	10,482	4,102	8,326
Allowance for loan losses
Balance, beginning of period		5,879	5,879
Provision for credit losses			4,216
ACL Loans
Provision for credit losses, ACL Loans	2,149	431
Commercial and commercial real estate \| ASU 2016-13 \| Impact from adoption of ASU
Allowance for credit losses
Balance, beginning of period		(1,277)	(1,277)
Agricultural production and real estate
Allowance for credit losses
Balance, beginning of period	565
Provision for credit losses	(22)	(42)
Balance, end of period	543	597	565
Allowance for loan losses
Balance, beginning of period		657	657
Provision for credit losses			(74)
ACL Loans
Provision for credit losses, ACL Loans	(22)	(42)
Agricultural production and real estate \| ASU 2016-13 \| Impact from adoption of ASU
Allowance for credit losses
Balance, beginning of period		(18)	(18)
Consumer and margin loans
Allowance for credit losses
Balance, beginning of period	182
Provision for credit losses	(15)
Loans charged to the allowance			(15)
Recoveries of loans previously charged off		7	7
Balance, end of period	167	166	182
Allowance for loan losses
Balance, beginning of period		138	138
Provision for credit losses			31
ACL Loans
Provision for credit losses, ACL Loans	$ (15)
Consumer and margin loans \| ASU 2016-13 \| Impact from adoption of ASU
Allowance for credit losses
Balance, beginning of period		$ 21	$ 21

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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Amount of increase in allowance for credit loss on financing receivable from recovery.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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Amount of expense related to estimated loss from loan and lease transactions.

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Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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Amount of credit loss expense (reversal of expense) for financing receivable.

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