Loans and Allowance for Loan and Lease Losses - Schedule of Non-Accrual Loans and Troubled Debt Restructurings (TDR) by Class of Loans (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2017	Dec. 31, 2016
Accounts Notes And Loans Receivable [Line Items]
Non-Accrual	$ 13,624	$ 3,619
Troubled Debt Restructurings	1,256	1,272
Commercial real estate
Accounts Notes And Loans Receivable [Line Items]
Non-Accrual	1,287	1,310
Troubled Debt Restructurings	1,256	1,272
Commercial and industrial
Accounts Notes And Loans Receivable [Line Items]
Non-Accrual	$ 12,337	$ 2,309

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

Reflects the amount of the write-down related to a troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18845-111554

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- Definition

Reflects the carrying amount of loans deemed to be questionable as to collection on which no interest is continuing to be recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5111-111524

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