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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Loans and Allowance for Loan Losses - Summary of Loans By Classification (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Loans and Allowance for Loan Losses
Loans	$ 4,880,990		$ 3,028,310
Allowance for loan losses	23,436	$ 20,497	15,842	$ 13,705	$ 12,604	$ 12,704
Loans and Leases Receivable, Net Amount, Total	4,857,554		3,012,468
Mortgage warehouse lines of credit
Loans and Allowance for Loan Losses
Loans	1,647,521		765,151
Allowance for loan losses	4,077	3,203	1,913	1,991	1,565	1,068
Residential real estate
Loans and Allowance for Loan Losses
Loans	572,527		413,835
Allowance for loan losses	2,814	2,310	2,042	1,992	1,929	1,986
Multi-family and healthcare financing
Loans and Allowance for Loan Losses
Loans	2,125,516		1,347,125
Allowance for loan losses	11,444	9,878	7,018	5,897	5,144	6,030
Commercial and commercial real estate
Loans and Allowance for Loan Losses
Loans	419,812		398,601
Allowance for loan losses	4,324	4,343	4,173	3,112	3,271	3,051
Agricultural production and real estate
Loans and Allowance for Loan Losses
Loans	101,636		85,210
Allowance for loan losses	631	610	523	529	515	429
Consumer and margin loans
Loans and Allowance for Loan Losses
Loans	13,978		18,388
Allowance for loan losses	$ 146	$ 153	$ 173	$ 184	$ 180	$ 140