Loans and Allowance for Loan and Lease Losses - Schedule of Outstanding Contractually Required Principal and Interest and Carrying Amount of PCI Loans Receivable (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Accounts Notes And Loans Receivable [Line Items]
Outstanding contractually required principal and interest	$ 19,037	$ 34,716
Loans	2,425,463	2,027,624
Real Estate Loans
Accounts Notes And Loans Receivable [Line Items]
Outstanding contractually required principal and interest	17,447	25,013
Commercial Loans
Accounts Notes And Loans Receivable [Line Items]
Outstanding contractually required principal and interest	1,590	9,703
Loans	890,372	778,643
Purchased Credit Impaired Loans
Accounts Notes And Loans Receivable [Line Items]
Loans	14,955	26,907
Purchased Credit Impaired Loans \| Commercial Loans
Accounts Notes And Loans Receivable [Line Items]
Loans	$ 838	$ 7,522

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.

No definition available.

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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82894507&loc=d3e13503-111538

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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