Loans and Allowance for Credit Losses on Loans - Aging Analysis Of The Recorded Investment In Loans (Details)	Jun. 30, 2022 USD ($) loan	Dec. 31, 2021 USD ($) loan
Aging analysis of loan portfolio
Loans	$ 7,070,677,000
Loans		$ 5,782,663,000
Number of loans modified in accordance with CARES Act \| loan	1	1
Amount of outstanding loans modified in accordance with CARES Act	$ 36,800,000	$ 36,800,000
Loans modified in accordance with CARES Act, payments due	0
Total Past Due
Aging analysis of loan portfolio
Loans	4,866,000
Loans		2,619,000
30-59 Days Past Due
Aging analysis of loan portfolio
Loans	346,000
Loans		1,923,000
60-89 Days Past Due
Aging analysis of loan portfolio
Loans	258,000
Loans		321,000
Greater Than 90 Days
Aging analysis of loan portfolio
Loans	4,262,000
Loans		375,000
Current.
Aging analysis of loan portfolio
Loans	7,065,811,000
Loans		5,780,044,000
Mortgage warehouse lines of credit
Aging analysis of loan portfolio
Loans	900,585,000
Loans		781,437,000
Mortgage warehouse lines of credit \| Current.
Aging analysis of loan portfolio
Loans	900,585,000
Loans		781,437,000
Residential real estate
Aging analysis of loan portfolio
Loans	876,652,000
Loans		843,101,000
Residential real estate \| Total Past Due
Aging analysis of loan portfolio
Loans	699,000
Loans		1,725,000
Residential real estate \| 30-59 Days Past Due
Aging analysis of loan portfolio
Loans	307,000
Loans		1,252,000
Residential real estate \| 60-89 Days Past Due
Aging analysis of loan portfolio
Loans	216,000
Loans		287,000
Residential real estate \| Greater Than 90 Days
Aging analysis of loan portfolio
Loans	176,000
Loans		186,000
Residential real estate \| Current.
Aging analysis of loan portfolio
Loans	875,953,000
Loans		841,376,000
Healthcare financing
Aging analysis of loan portfolio
Loans	1,262,424,000
Loans		826,157,000
Healthcare financing \| Current.
Aging analysis of loan portfolio
Loans	1,262,424,000
Loans		826,157,000
Multi-family financing
Aging analysis of loan portfolio
Loans	3,236,917,000
Loans		2,702,042,000
Multi-family financing \| Current.
Aging analysis of loan portfolio
Loans	3,236,917,000
Loans		2,702,042,000
Commercial and commercial real estate
Aging analysis of loan portfolio
Loans	695,158,000
Loans		520,199,000
Commercial and commercial real estate \| Total Past Due
Aging analysis of loan portfolio
Loans	4,083,000
Loans		748,000
Commercial and commercial real estate \| 30-59 Days Past Due
Aging analysis of loan portfolio
Loans		591,000
Commercial and commercial real estate \| 60-89 Days Past Due
Aging analysis of loan portfolio
Loans		8,000
Commercial and commercial real estate \| Greater Than 90 Days
Aging analysis of loan portfolio
Loans	4,083,000
Loans		149,000
Commercial and commercial real estate \| Current.
Aging analysis of loan portfolio
Loans	691,075,000
Loans		519,451,000
Commercial and commercial real estate \| Government guaranteed SBA loans \| 30-59 Days Past Due
Aging analysis of loan portfolio
Loans	0
Loans		3,200,000
Commercial and commercial real estate \| Government guaranteed SBA loans \| Greater Than 90 Days
Aging analysis of loan portfolio
Loans	0
Loans		274,000
Agricultural production and real estate
Aging analysis of loan portfolio
Loans	90,070,000
Loans		97,060,000
Agricultural production and real estate \| Total Past Due
Aging analysis of loan portfolio
Loans		58,000
Agricultural production and real estate \| 30-59 Days Past Due
Aging analysis of loan portfolio
Loans		37,000
Agricultural production and real estate \| 60-89 Days Past Due
Aging analysis of loan portfolio
Loans		21,000
Agricultural production and real estate \| Current.
Aging analysis of loan portfolio
Loans	90,070,000
Loans		97,002,000
Consumer and margin loans
Aging analysis of loan portfolio
Loans	8,871,000
Loans		12,667,000
Consumer and margin loans \| Total Past Due
Aging analysis of loan portfolio
Loans	84,000
Loans		88,000
Consumer and margin loans \| 30-59 Days Past Due
Aging analysis of loan portfolio
Loans	39,000
Loans		43,000
Consumer and margin loans \| 60-89 Days Past Due
Aging analysis of loan portfolio
Loans	42,000
Loans		5,000
Consumer and margin loans \| Greater Than 90 Days
Aging analysis of loan portfolio
Loans	3,000
Loans		40,000
Consumer and margin loans \| Current.
Aging analysis of loan portfolio
Loans	$ 8,787,000
Loans		$ 12,579,000

The number of loans modified in accordance with the CARES Act.

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Amount excluding accrued interest, before allowance for credit loss, of financing receivable.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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