Loan and Lease Receivables - Summary of Outstanding Balance and Carrying Amount of All Acquired Impaired Loans (Details) - Acquired Impaired Loans - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Accounts Notes And Loans Receivable [Line Items]
Outstanding Balance	$ 326,684	$ 380,880
Carrying Value	216,818	258,668
Commercial Real Estate
Accounts Notes And Loans Receivable [Line Items]
Outstanding Balance	163,146	189,969
Carrying Value	117,114	135,914
Residential Real Estate
Accounts Notes And Loans Receivable [Line Items]
Outstanding Balance	132,232	151,641
Carrying Value	84,197	100,223
Construction, Land Development, and Other Land
Accounts Notes And Loans Receivable [Line Items]
Outstanding Balance	14,085	14,841
Carrying Value	4,804	5,373
Commercial and Industrial
Accounts Notes And Loans Receivable [Line Items]
Outstanding Balance	16,287	23,330
Carrying Value	10,489	16,909
Installment and Other
Accounts Notes And Loans Receivable [Line Items]
Outstanding Balance	934	1,099
Carrying Value	$ 214	$ 249

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No definition available.

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- Definition

The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and allowance for loan losses). This relates to loans not accounted for debt securities with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=118939070&loc=d3e15032-111544

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118938799&loc=d3e13503-111538

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- Definition

The undiscounted sum of all amounts, including amounts deemed principal, interest, fees, penalties, and other under the loan, owed to the investor at the reporting date, whether or not currently due and whether or not any such amounts have been written or charged off by the investor. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118938799&loc=d3e13503-111538

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=118939070&loc=d3e15032-111544

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