Loans and Allowance for Loan Losses - Summary of Loans By Classification (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Loans and Allowance for Loan Losses
Loans	$ 3,520,653	$ 3,028,310
Allowance for loan losses	18,883	15,842	$ 13,356	$ 12,704
Loans and Leases Receivable, Net Amount, Total	3,501,770	3,012,468
Mortgage warehouse lines of credit
Loans and Allowance for Loan Losses
Loans	1,083,776	765,151
Allowance for loan losses	2,709	1,913	1,254	1,068
Residential real estate
Loans and Allowance for Loan Losses
Loans	421,978	413,835
Allowance for loan losses	2,062	2,042	1,990	1,986
Multi-family and healthcare financing
Loans and Allowance for Loan Losses
Loans	1,435,206	1,347,125
Allowance for loan losses	7,694	7,018	6,377	6,030
Commercial and commercial real estate
Loans and Allowance for Loan Losses
Loans	468,668	398,601
Allowance for loan losses	5,662	4,173	3,122	3,051
Agricultural production and real estate
Loans and Allowance for Loan Losses
Loans	92,498	85,210
Allowance for loan losses	561	523	466	429
Consumer and margin loans
Loans and Allowance for Loan Losses
Loans	18,527	18,388
Allowance for loan losses	$ 195	$ 173	$ 147	$ 140

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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