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, 2019	Dec. 31, 2018
Accounts Notes And Loans Receivable [Line Items]
Outstanding Balance	$ 399,954	$ 428,768
Carrying Value	275,022	277,542
Commercial Real Estate
Accounts Notes And Loans Receivable [Line Items]
Outstanding Balance	196,495	216,137
Carrying Value	142,435	146,808
Residential Real Estate
Accounts Notes And Loans Receivable [Line Items]
Outstanding Balance	161,742	173,962
Carrying Value	109,409	113,934
Construction, Land Development, and Other Land
Accounts Notes And Loans Receivable [Line Items]
Outstanding Balance	13,276	11,962
Carrying Value	4,562	3,779
Commercial and Industrial
Accounts Notes And Loans Receivable [Line Items]
Outstanding Balance	27,320	24,972
Carrying Value	18,349	12,617
Installment and Other
Accounts Notes And Loans Receivable [Line Items]
Outstanding Balance	1,121	1,735
Carrying Value	$ 267	$ 404

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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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