Allowance for Loan and Lease Losses and Reserve for Unfunded Commitments - Summary of Allowance for Loan and Lease Losses and Corresponding Loan and Lease Balances (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	$ 61,719	$ 51,300	$ 66,347	$ 31,936
Provisions (recapture)	352	15,740	2,750	45,713
Charge-offs	2,484	6,145	10,366	17,615
Recoveries	1,011	363	1,867	1,224
Ending balance	60,598	61,258	60,598	61,258
Individually evaluated for impairment	24,562	14,782	24,562	14,782
Collectively evaluated for impairment	31,761	41,445	31,761	41,445
Allowance for loan and lease losses	60,598	61,258	60,598	61,258	$ 66,347
Individually evaluated for impairment	87,198	77,890	87,198	77,890
Collectively evaluated for impairment	4,366,750	4,079,809	4,366,750	4,079,809
Total loans and leases	4,609,228	4,374,517	4,609,228	4,374,517	4,340,535
Loans Acquired with Deteriorated Credit Quality
Financing Receivable Allowance For Credit Losses [Line Items]
Loans acquired with deteriorated credit quality	4,275	5,031	4,275	5,031
Loans acquired with deteriorated credit quality	155,280	216,818	155,280	216,818
Commercial Real Estate
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	19,541	14,110	19,584	7,965
Provisions (recapture)	(1,108)	6,421	2,891	14,149
Charge-offs	564	1,566	2,644	3,206
Recoveries	287	19	541	76
Ending balance	20,372	18,984	20,372	18,984
Individually evaluated for impairment	8,420	4,516	8,420	4,516
Collectively evaluated for impairment	9,314	11,825	9,314	11,825
Allowance for loan and lease losses	20,372	18,984	20,372	18,984	19,584
Individually evaluated for impairment	45,563	39,001	45,563	39,001
Collectively evaluated for impairment	1,487,994	1,191,740	1,487,994	1,191,740
Total loans and leases	1,618,378	1,347,855	1,618,378	1,347,855	1,421,670
Commercial Real Estate \| Loans Acquired with Deteriorated Credit Quality
Financing Receivable Allowance For Credit Losses [Line Items]
Loans acquired with deteriorated credit quality	2,638	2,643	2,638	2,643
Loans acquired with deteriorated credit quality	84,821	117,114	84,821	117,114
Residential Real Estate
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	1,364	3,741	2,400	1,990
Provisions (recapture)	(225)	291	(1,257)	2,031
Charge-offs	(65)	250	76	259
Recoveries	2	8	9	28
Ending balance	1,076	3,790	1,076	3,790
Individually evaluated for impairment	0	77	0	77
Collectively evaluated for impairment	723	3,413	723	3,413
Allowance for loan and lease losses	1,076	3,790	1,076	3,790	2,400
Individually evaluated for impairment	3,946	1,636	3,946	1,636
Collectively evaluated for impairment	441,915	547,563	441,915	547,563
Total loans and leases	507,754	633,396	507,754	633,396	572,271
Residential Real Estate \| Loans Acquired with Deteriorated Credit Quality
Financing Receivable Allowance For Credit Losses [Line Items]
Loans acquired with deteriorated credit quality	353	300	353	300
Loans acquired with deteriorated credit quality	61,893	84,197	61,893	84,197
Construction, Land Development, and Other Land
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	619	1,491	1,352	610
Provisions (recapture)	(61)	1,029	(468)	1,910
Charge-offs	0	(701)	326	(701)
Recoveries	0	53	0	53
Ending balance	558	1,872	558	1,872
Individually evaluated for impairment	0	0	0	0
Collectively evaluated for impairment	550	1,685	550	1,685
Allowance for loan and lease losses	558	1,872	558	1,872	1,352
Individually evaluated for impairment	0	0	0	0
Collectively evaluated for impairment	336,666	234,230	336,666	234,230
Total loans and leases	338,412	239,034	338,412	239,034	230,733
Construction, Land Development, and Other Land \| Loans Acquired with Deteriorated Credit Quality
Financing Receivable Allowance For Credit Losses [Line Items]
Loans acquired with deteriorated credit quality	8	187	8	187
Loans acquired with deteriorated credit quality	1,746	4,804	1,746	4,804
Commercial and Industrial
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	38,284	30,108	41,183	19,377
Provisions (recapture)	(1,218)	7,603	226	26,844
Charge-offs	1,456	3,254	6,172	12,057
Recoveries	380	83	753	376
Ending balance	35,990	34,540	35,990	34,540
Individually evaluated for impairment	16,142	10,189	16,142	10,189
Collectively evaluated for impairment	18,572	22,450	18,572	22,450
Allowance for loan and lease losses	35,990	34,540	35,990	34,540	41,183
Individually evaluated for impairment	37,689	37,253	37,689	37,253
Collectively evaluated for impairment	1,492,065	1,281,067	1,492,065	1,281,067
Total loans and leases	1,536,405	1,328,809	1,536,405	1,328,809	1,368,900
Commercial and Industrial \| Loans Acquired with Deteriorated Credit Quality
Financing Receivable Allowance For Credit Losses [Line Items]
Loans acquired with deteriorated credit quality	1,276	1,901	1,276	1,901
Loans acquired with deteriorated credit quality	6,651	10,489	6,651	10,489
Paycheck Protection Program
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	0	0	0	0
Provisions (recapture)	0	0	0	0
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	0	0	0	0
Individually evaluated for impairment	0	0	0	0
Collectively evaluated for impairment	0	0	0	0
Allowance for loan and lease losses	0	0	0	0	0
Individually evaluated for impairment	0	0	0	0
Collectively evaluated for impairment	268,081	622,191	268,081	622,191
Total loans and leases	268,081	622,191	268,081	622,191	517,815
Paycheck Protection Program \| Loans Acquired with Deteriorated Credit Quality
Financing Receivable Allowance For Credit Losses [Line Items]
Loans acquired with deteriorated credit quality	0	0	0	0
Loans acquired with deteriorated credit quality	0	0	0	0
Installment and Other
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	9	36	15	50
Provisions (recapture)	(2)	(1)	(8)	(13)
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	7	37	7	37
Individually evaluated for impairment	0	0	0	0
Collectively evaluated for impairment	7	37	7	37
Allowance for loan and lease losses	7	37	7	37	15
Individually evaluated for impairment	0	0	0	0
Collectively evaluated for impairment	1,273	2,929	1,273	2,929
Total loans and leases	1,442	3,143	1,442	3,143	2,005
Installment and Other \| Loans Acquired with Deteriorated Credit Quality
Financing Receivable Allowance For Credit Losses [Line Items]
Loans acquired with deteriorated credit quality	0	0	0	0
Loans acquired with deteriorated credit quality	169	214	169	214
Lease Financing Receivables
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	1,902	1,814	1,813	1,944
Provisions (recapture)	750	395	1,366	792
Charge-offs	399	374	1,148	1,392
Recoveries	342	200	564	691
Ending balance	2,595	2,035	2,595	2,035
Individually evaluated for impairment	0	0	0	0
Collectively evaluated for impairment	2,595	2,035	2,595	2,035
Allowance for loan and lease losses	2,595	2,035	2,595	2,035	1,813
Individually evaluated for impairment	0	0	0	0
Collectively evaluated for impairment	338,756	200,089	338,756	200,089
Total loans and leases	338,756	200,089	338,756	200,089	$ 227,141
Lease Financing Receivables \| Loans Acquired with Deteriorated Credit Quality
Financing Receivable Allowance For Credit Losses [Line Items]
Loans acquired with deteriorated credit quality	0	0	0	0
Loans acquired with deteriorated credit quality	$ 0	$ 0	$ 0	$ 0

Financing receivable allowance for loans and leases acquired deteriorated credit quality.

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Financing receivable allowance for loans and losses collectively evaluated for impairment.

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Financing receivable allowance for loans and losses individually evaluated for impairment.

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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 balance of financing receivables that were collectively evaluated for impairment.

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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 of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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

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

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