Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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

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Amount, before allowance for credit loss, of financing receivable.

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Loans and Allowance for Credit Losses - Summary of Individual and Collective Allowance for Loan Losses and Loan Balances by Class (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Financing Receivable, Allowance for Credit Loss [Line Items]
Loan Evaluation, Individually			$ 49,851
Loan Evaluation, Collectively			4,131,986
Loans	$ 4,852,911		4,194,512
ALLL Allocations, Individually			5,113
ALLL Allocations, Collectively			23,975
Allowance for credit losses	90,995	$ 54,613	29,092	$ 31,895	$ 29,416	$ 27,571
Purchased Credit Impaired Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans			12,675
Allowance for credit losses			4
Commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Loan Evaluation, Individually			7,455
Loan Evaluation, Collectively			1,030,439
Loans	762,531		1,046,961
ALLL Allocations, Individually			344
ALLL Allocations, Collectively			5,009
Allowance for credit losses	13,152	15,539	5,353	5,798	5,677	4,493
Commercial real estate \| Purchased Credit Impaired Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans			9,067
Allowance for credit losses			0
Construction, land development, land
Financing Receivable, Allowance for Credit Loss [Line Items]
Loan Evaluation, Individually			2,138
Loan Evaluation, Collectively			155,985
Loans	244,512		160,569
ALLL Allocations, Individually			271
ALLL Allocations, Collectively			1,111
Allowance for credit losses	5,600	5,917	1,382	1,084	1,035	1,134
Construction, land development, land \| Purchased Credit Impaired Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans			2,446
Allowance for credit losses			0
1-4 family residential
Financing Receivable, Allowance for Credit Loss [Line Items]
Loan Evaluation, Individually			1,728
Loan Evaluation, Collectively			177,189
Loans	164,785		179,425
ALLL Allocations, Individually			33
ALLL Allocations, Collectively			275
Allowance for credit losses	1,972	2,027	308	417	409	317
1-4 family residential \| Purchased Credit Impaired Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans			508
Allowance for credit losses			0
Farmland
Financing Receivable, Allowance for Credit Loss [Line Items]
Loan Evaluation, Individually			6,638
Loan Evaluation, Collectively			148,233
Loans	110,966		154,975
ALLL Allocations, Individually			0
ALLL Allocations, Collectively			670
Allowance for credit losses	863	958	670	939	590	535
Farmland \| Purchased Credit Impaired Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans			104
Allowance for credit losses			0
Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Loan Evaluation, Individually			15,618
Loan Evaluation, Collectively			1,326,515
Loans	1,536,903		1,342,683
ALLL Allocations, Individually			1,278
ALLL Allocations, Collectively			11,284
Allowance for credit losses	22,713	23,283	12,566	14,771	13,899	12,865
Commercial \| Purchased Credit Impaired Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans			550
Allowance for credit losses			4
Factored receivables
Financing Receivable, Allowance for Credit Loss [Line Items]
Loan Evaluation, Individually			15,947
Loan Evaluation, Collectively			604,039
Loans	1,016,337		619,986
ALLL Allocations, Individually			3,178
ALLL Allocations, Collectively			4,479
Allowance for credit losses	44,985	5,244	7,657	7,717	6,861	7,299
Factored receivables \| Purchased Credit Impaired Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans			0
Allowance for credit losses			0
Consumer
Financing Receivable, Allowance for Credit Loss [Line Items]
Loan Evaluation, Individually			327
Loan Evaluation, Collectively			21,598
Loans	17,106		21,925
ALLL Allocations, Individually			9
ALLL Allocations, Collectively			479
Allowance for credit losses	710	768	488	581	563	615
Consumer \| Purchased Credit Impaired Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans			0
Allowance for credit losses			0
Mortgage warehouse
Financing Receivable, Allowance for Credit Loss [Line Items]
Loan Evaluation, Individually			0
Loan Evaluation, Collectively			667,988
Loans	999,771		667,988
ALLL Allocations, Individually			0
ALLL Allocations, Collectively			668
Allowance for credit losses	$ 1,000	$ 877	668	$ 588	$ 382	$ 313
Mortgage warehouse \| Purchased Credit Impaired Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans			0
Allowance for credit losses			$ 0