Loans and Allowance for Loan Losses - Allowance For Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Allowance for loan losses
Balance, beginning of period	$ 15,842	$ 12,704
Provision (credit) for loan losses	2,998	649
Loans charged to the allowance	(1)
Recoveries of loans previously charged off	44	3
Balance, end of period	18,883	13,356
Ending balance: individually evaluated for impairment	1,202		$ 681
Ending balance: collectively evaluated for impairment	17,681		15,161
Loans
Ending balance	3,520,653		3,028,310
Ending balance individually evaluated for impairment	14,124		12,517
Ending balance: collectively evaluated for impairment	3,506,529		3,015,793
Mortgage warehouse lines of credit
Allowance for loan losses
Balance, beginning of period	1,913	1,068
Provision (credit) for loan losses	796	186
Balance, end of period	2,709	1,254
Ending balance: collectively evaluated for impairment	2,709		1,913
Loans
Ending balance	1,083,776		765,151
Ending balance individually evaluated for impairment	230		233
Ending balance: collectively evaluated for impairment	1,083,546		764,918
Residential real estate
Allowance for loan losses
Balance, beginning of period	2,042	1,986
Provision (credit) for loan losses	20	4
Balance, end of period	2,062	1,990
Ending balance: individually evaluated for impairment	29		23
Ending balance: collectively evaluated for impairment	2,033		2,019
Loans
Ending balance	421,978		413,835
Ending balance individually evaluated for impairment	2,410		3,109
Ending balance: collectively evaluated for impairment	419,568		410,726
Multi-family and healthcare financing
Allowance for loan losses
Balance, beginning of period	7,018	6,030
Provision (credit) for loan losses	676	347
Balance, end of period	7,694	6,377
Ending balance: collectively evaluated for impairment	7,694		7,018
Loans
Ending balance	1,435,206		1,347,125
Ending balance: collectively evaluated for impairment	1,435,206		1,347,125
Commercial and commercial real estate
Allowance for loan losses
Balance, beginning of period	4,173	3,051
Provision (credit) for loan losses	1,445	71
Recoveries of loans previously charged off	44
Balance, end of period	5,662	3,122
Ending balance: individually evaluated for impairment	1,167		650
Ending balance: collectively evaluated for impairment	4,495		3,523
Loans
Ending balance	468,668		398,601
Ending balance individually evaluated for impairment	9,425		9,152
Ending balance: collectively evaluated for impairment	459,243		389,449
Agricultural production and real estate
Allowance for loan losses
Balance, beginning of period	523	429
Provision (credit) for loan losses	38	34
Recoveries of loans previously charged off		3
Balance, end of period	561	466
Ending balance: collectively evaluated for impairment	561		523
Loans
Ending balance	92,498		85,210
Ending balance individually evaluated for impairment	2,043
Ending balance: collectively evaluated for impairment	90,455		85,210
Consumer and margin loans
Allowance for loan losses
Balance, beginning of period	173	140
Provision (credit) for loan losses	23	7
Loans charged to the allowance	(1)
Balance, end of period	195	$ 147
Ending balance: individually evaluated for impairment	6		8
Ending balance: collectively evaluated for impairment	189		165
Loans
Ending balance	18,527		18,388
Ending balance individually evaluated for impairment	16		23
Ending balance: collectively evaluated for impairment	$ 18,511		$ 18,365

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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

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