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
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021	Sep. 30, 2021
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	$ (55,012)	$ (66,347)
Provisions (recapture)	4,995	4,367
Charge-offs	(1,066)	(5,466)
Recoveries	517	342
Ending balance	59,458	65,590
Individually evaluated for impairment	20,739	26,334
Collectively evaluated for impairment	35,673	35,101
Loans acquired with deteriorated credit quality	3,046	4,155
Allowance for loan and lease losses	59,458	65,590	$ 55,012
Individually evaluated for impairment	71,452	99,436
Collectively evaluated for impairment	4,597,865	4,173,817
Total loans and leases	4,789,068	4,454,620	4,537,128
Loans Acquired with Deteriorated Credit Quality
Financing Receivable Allowance For Credit Losses [Line Items]
Loans acquired with deteriorated credit quality	119,751	181,367
Commercial Real Estate
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	(16,918)	(19,584)
Provisions (recapture)	2,784	2,606
Charge-offs	(240)	(1,877)
Recoveries	244	185
Ending balance	19,706	20,498
Individually evaluated for impairment	7,731	7,409
Collectively evaluated for impairment	10,320	10,881
Loans acquired with deteriorated credit quality	1,655	2,208
Allowance for loan and lease losses	19,706	20,498	16,918
Individually evaluated for impairment	36,805	54,421
Collectively evaluated for impairment	1,675,468	1,281,188
Total loans and leases	1,779,365	1,431,668	1,665,748
Commercial Real Estate \| Loans Acquired with Deteriorated Credit Quality
Financing Receivable Allowance For Credit Losses [Line Items]
Loans acquired with deteriorated credit quality	67,092	96,059
Residential Real Estate
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	1,628	2,400
Provisions (recapture)	513	(302)
Charge-offs	0	(11)
Recoveries	4	4
Ending balance	2,145	2,091
Individually evaluated for impairment	6	101
Collectively evaluated for impairment	1,138	1,460
Loans acquired with deteriorated credit quality	1,001	530
Allowance for loan and lease losses	2,145	2,091	(1,628)
Individually evaluated for impairment	2,190	1,709
Collectively evaluated for impairment	445,183	469,287
Total loans and leases	494,720	545,279	480,514
Residential Real Estate \| Loans Acquired with Deteriorated Credit Quality
Financing Receivable Allowance For Credit Losses [Line Items]
Loans acquired with deteriorated credit quality	47,347	74,283
Construction, Land Development, and Other Land
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	(522)	(1,352)
Provisions (recapture)	594	(241)
Charge-offs	0	(326)
Recoveries	0	0
Ending balance	1,116	785
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	1,115	780
Loans acquired with deteriorated credit quality	1	5
Allowance for loan and lease losses	1,116	785	522
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	351,715	238,332
Total loans and leases	353,072	240,324	325,399
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	1,357	1,992
Commercial and Industrial
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	(33,129)	(41,183)
Provisions (recapture)	(458)	1,947
Charge-offs	463	2,888
Recoveries	120	60
Ending balance	33,244	40,302
Individually evaluated for impairment	13,002	18,824
Collectively evaluated for impairment	19,855	20,066
Loans acquired with deteriorated credit quality	387	1,412
Allowance for loan and lease losses	33,244	40,302	33,129
Individually evaluated for impairment	32,457	43,306
Collectively evaluated for impairment	1,703,362	1,312,248
Total loans and leases	1,739,611	1,364,396	1,581,961
Commercial and Industrial \| Loans Acquired with Deteriorated Credit Quality
Financing Receivable Allowance For Credit Losses [Line Items]
Loans acquired with deteriorated credit quality	3,792	8,842
Paycheck Protection Program
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	0	0
Provisions (recapture)	0	0
Charge-offs	0	0
Recoveries	0	0
Ending balance	0	0
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	0	0
Loans acquired with deteriorated credit quality		0
Allowance for loan and lease losses	0	0	0
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	36,260	617,006
Loans acquired with deteriorated credit quality	0
Total loans and leases	36,260	617,006	123,712
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
Installment and Other
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	(9)	(15)
Provisions (recapture)	(1)	(3)
Charge-offs	0	0
Recoveries	0	0
Ending balance	10	12
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	8	12
Loans acquired with deteriorated credit quality	2	0
Allowance for loan and lease losses	10	12	9
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	1,193	1,425
Total loans and leases	1,356	1,616	1,368
Installment and Other \| Loans Acquired with Deteriorated Credit Quality
Financing Receivable Allowance For Credit Losses [Line Items]
Loans acquired with deteriorated credit quality	163	191
Lease Financing Receivables
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	(2,806)	(1,813)
Provisions (recapture)	645	360
Charge-offs	(363)	(364)
Recoveries	149	93
Ending balance	3,237	1,902
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	3,237	1,902
Loans acquired with deteriorated credit quality	0	0
Allowance for loan and lease losses	3,237	1,902	2,806
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	384,684	254,331
Total loans and leases	384,684	254,331	$ 358,426	$ 384,684
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

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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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

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

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- Definition

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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