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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-3B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (b)
-Publisher FASB
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Loans and Allowance for Credit Losses on Loans - Amortized cost basis and ACL (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	$ 10,766,225	$ 10,199,553
ACL-Loans	75,712	71,752	$ 51,838	$ 44,014
Collateral Dependent Loans
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	123,355	128,627
ACL-Loans	8,022	7,964
Real Estate
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	118,070	122,334
Accounts Receivable Or Equipment
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	2,628	3,603
Other Collateralized Assets
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	2,657	2,690
Residential real estate
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	1,321,300	1,324,305
ACL-Loans	6,905	7,323	7,378	7,029
Residential real estate \| Collateral Dependent Loans
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	1,272	1,560
ACL-Loans	8	21
Residential real estate \| Real Estate
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	1,272	1,557
Residential real estate \| Other Collateralized Assets
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis		3
Multi-family financing
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	4,096,606	4,006,160
ACL-Loans	28,664	26,874	19,851	16,781
Multi-family financing \| Collateral Dependent Loans
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	53,200	46,575
ACL-Loans	581	521
Multi-family financing \| Real Estate
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	53,200	46,575
Healthcare financing
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	2,464,685	2,356,689
ACL-Loans	24,587	22,454	11,753	9,882
Healthcare financing \| Collateral Dependent Loans
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	63,283	73,909
ACL-Loans	5,652	6,289
Healthcare financing \| Real Estate
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	63,283	73,909
Commercial and commercial real estate
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	1,666,751	1,643,081
ACL-Loans	11,990	12,243	10,482	8,326
Commercial and commercial real estate \| Collateral Dependent Loans
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	5,453	6,433
ACL-Loans	1,780	1,132
Commercial and commercial real estate \| Real Estate
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	168	146
Commercial and commercial real estate \| Accounts Receivable Or Equipment
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	2,628	3,603
Commercial and commercial real estate \| Other Collateralized Assets
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	2,657	2,684
Agricultural production and real estate
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	65,977	103,150
ACL-Loans	450	619	543	565
Agricultural production and real estate \| Collateral Dependent Loans
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	147	147
ACL-Loans	1	1
Agricultural production and real estate \| Real Estate
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	147	147
Consumer and margin loans
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	7,912	13,700
ACL-Loans	$ 94	169	$ 167	$ 182
Consumer and margin loans \| Collateral Dependent Loans
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis		3
Consumer and margin loans \| Other Collateralized Assets
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis		$ 3