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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
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-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-3B

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-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	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	$ 9,917,004		$ 7,470,872
Allowance for credit losses on loans	62,986	$ 51,838	44,014	$ 37,474	$ 32,102	$ 31,344
Collateral Dependent Loans
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	79,506
Allowance for credit losses on loans	3,764
Real Estate
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	72,374
Accounts Receivable Or Equipment
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	3,830
Other Collateralized Assets
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	3,302
Mortgage warehouse lines of credit
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	1,201,932		464,785
Allowance for credit losses on loans	3,361	1,664	1,249	2,422	1,941	1,955
Residential real estate
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	1,342,586		1,178,401
Allowance for credit losses on loans	7,413	7,378	7,029	4,910	4,547	4,170
Residential real estate \| Collateral Dependent Loans
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	212
Allowance for credit losses on loans	36
Residential real estate \| Real Estate
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	209
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	3,746,333		3,135,535
Allowance for credit losses on loans	24,701	19,851	16,781	16,364	15,131	14,084
Multi-family financing \| Collateral Dependent Loans
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	41,335
Allowance for credit losses on loans	234
Multi-family financing \| Real Estate
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	41,335
Healthcare financing
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	2,128,378		1,604,341
Allowance for credit losses on loans	16,123	11,753	9,882	7,936	5,618	4,461
Healthcare financing \| Collateral Dependent Loans
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	30,683
Allowance for credit losses on loans	2,348
Healthcare financing \| Real Estate
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	30,683
Commercial and commercial real estate
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	1,394,256		978,661
Allowance for credit losses on loans	10,695	10,482	8,326	5,195	4,102	5,879
Commercial and commercial real estate \| Collateral Dependent Loans
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	7,124
Allowance for credit losses on loans	1,145
Commercial and commercial real estate \| Accounts Receivable Or Equipment
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	3,830
Commercial and commercial real estate \| Other Collateralized Assets
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	3,294
Agricultural production and real estate
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	91,599		95,651
Allowance for credit losses on loans	556	543	565	551	597	657
Agricultural production and real estate \| Collateral Dependent Loans
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	147
Allowance for credit losses on loans	1
Agricultural production and real estate \| Real Estate
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	147
Consumer and margin loans
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	11,920		13,498
Allowance for credit losses on loans	137	$ 167	$ 182	$ 96	$ 166	$ 138
Consumer and margin loans \| Collateral Dependent Loans
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	5
Consumer and margin loans \| Other Collateralized Assets
Loans and Allowance for Credit Losses on Loans
Amortized Cost Basis	$ 5