Loans and Allowance for Credit Losses - Summary of Allowance for Loan and Lease Losses (Details) - USD ($) $ in Thousands		3 Months Ended	9 Months Ended
Jan. 01, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	$ 29,092	$ 54,613	$ 29,416	$ 29,092	$ 27,571
Initial ACL on Loans Purchased with Credit Deterioration		37,415		37,415
Credit Loss Expense		(356)	2,865	27,974	7,560
Charge-offs		(1,425)	(878)	(4,637)	(4,107)
Recoveries		748	492	1,331	871
Reclassification to Held For Sale		0		(449)
Ending Balance		90,995	31,895	90,995	31,895
ASU 2016-13
Allowance for Loan and Lease Losses [Roll Forward]
Impact of Adopting ASC 326	269	0		269
Commercial real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	5,353	15,539	5,677	5,353	4,493
Initial ACL on Loans Purchased with Credit Deterioration		0		0
Credit Loss Expense		(2,440)	147	6,366	1,343
Charge-offs		0	(26)	0	(39)
Recoveries		53	0	61	1
Reclassification to Held For Sale		0		0
Ending Balance		13,152	5,798	13,152	5,798
Commercial real estate \| ASU 2016-13
Allowance for Loan and Lease Losses [Roll Forward]
Impact of Adopting ASC 326		0		1,372
Construction, land development, land
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	1,382	5,917	1,035	1,382	1,134
Initial ACL on Loans Purchased with Credit Deterioration		0		0
Credit Loss Expense		(319)	47	4,400	(63)
Charge-offs		0	0	0	(78)
Recoveries		2	2	5	91
Reclassification to Held For Sale		0		0
Ending Balance		5,600	1,084	5,600	1,084
Construction, land development, land \| ASU 2016-13
Allowance for Loan and Lease Losses [Roll Forward]
Impact of Adopting ASC 326		0		(187)
1-4 family residential
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	308	2,027	409	308	317
Initial ACL on Loans Purchased with Credit Deterioration		0		0
Credit Loss Expense		(56)	4	1,138	86
Charge-offs		(6)	0	(27)	(43)
Recoveries		7	4	40	57
Reclassification to Held For Sale		0		0
Ending Balance		1,972	417	1,972	417
1-4 family residential \| ASU 2016-13
Allowance for Loan and Lease Losses [Roll Forward]
Impact of Adopting ASC 326		0		513
Farmland
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	670	958	590	670	535
Initial ACL on Loans Purchased with Credit Deterioration		0		0
Credit Loss Expense		(95)	349	(324)	404
Charge-offs		0	0	0	0
Recoveries		0	0	80	0
Reclassification to Held For Sale		0		0
Ending Balance		863	939	863	939
Farmland \| ASU 2016-13
Allowance for Loan and Lease Losses [Roll Forward]
Impact of Adopting ASC 326		0		437
Commercial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	12,566	23,283	13,899	12,566	12,865
Initial ACL on Loans Purchased with Credit Deterioration		0		0
Credit Loss Expense		(657)	1,195	11,004	3,252
Charge-offs		(528)	(557)	(1,173)	(1,671)
Recoveries		615	234	949	325
Reclassification to Held For Sale		0		(449)
Ending Balance		22,713	14,771	22,713	14,771
Commercial \| ASU 2016-13
Allowance for Loan and Lease Losses [Roll Forward]
Impact of Adopting ASC 326		0		(184)
Factored receivables
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	7,657	5,244	6,861	7,657	7,299
Initial ACL on Loans Purchased with Credit Deterioration		37,415		37,415
Credit Loss Expense		3,059	851	4,475	1,839
Charge-offs		(773)	(210)	(3,027)	(1,682)
Recoveries		40	215	95	261
Reclassification to Held For Sale		0		0
Ending Balance		44,985	7,717	44,985	7,717
Factored receivables \| ASU 2016-13
Allowance for Loan and Lease Losses [Roll Forward]
Impact of Adopting ASC 326		0		(1,630)
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	488	768	563	488	615
Initial ACL on Loans Purchased with Credit Deterioration		0		0
Credit Loss Expense		29	66	583	424
Charge-offs		(118)	(85)	(410)	(594)
Recoveries		31	37	101	136
Reclassification to Held For Sale		0		0
Ending Balance		710	581	710	581
Consumer \| ASU 2016-13
Allowance for Loan and Lease Losses [Roll Forward]
Impact of Adopting ASC 326		0		(52)
Mortgage warehouse
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	$ 668	877	382	668	313
Initial ACL on Loans Purchased with Credit Deterioration		0		0
Credit Loss Expense		123	206	332	275
Charge-offs		0	0	0	0
Recoveries		0	0	0	0
Reclassification to Held For Sale		0		0
Ending Balance		1,000	$ 588	1,000	$ 588
Mortgage warehouse \| ASU 2016-13
Allowance for Loan and Lease Losses [Roll Forward]
Impact of Adopting ASC 326		$ 0		$ 0

Amount of allowance for loan and lease losses reclassified to assets held for sale.

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New accounting pronouncement or change in accounting principle effect of change on loans and lease receivable allowance.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of increase in allowance for credit loss on financing receivable purchased with credit deterioration.

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

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Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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Amount of credit loss expense (reversal of expense) for financing receivable.

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