Borrowed Funds - Summary of Borrowed Funds (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Federal Home Loan Bank advances, Amount	$ 288,691	$ 250,498
Securities sold under agreements to repurchase, Amount	79,668	69,935
Other borrowings, Amount	56,519	56,559
Borrowed funds, Amount	$ 424,878	$ 376,992
Weighted Average
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Federal Home Loan Bank advances, Weighted Average Rate	1.74%	1.75%
Securities sold under agreements to repurchase, Weighted Average Rate	0.21%	0.13%
Other borrowings, Weighted Average Rate	4.48%	4.21%
Borrowed funds, Weighted Average Rate	1.82%	1.81%

Other Borrowings Weighted Average Rate

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- Definition

Securities Sold Under Repurchase Agreements Weighted Average Interest Rate

+ References

No definition available.

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- Definition

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
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Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

+ References

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States the interest rate applicable to Federal Home Loan Bank advances outstanding as of the Balance Sheet date.

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- Definition

Weighted average interest rate of long-term debt outstanding calculated at point in time.

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The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

+ References

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- Definition

Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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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.

+ References

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