Borrowings - Schedule of Borrowings (Detail) - USD ($)	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2017
Debt Disclosure [Abstract]
Securities sold under agreements with customers to repurchase	$ 389,010,000	$ 320,450,000	$ 309,524,000
Federal funds purchased	7,925,000	10,550,000	19,800,000
Advances from the Federal Home Loan Bank	60,000,000		50,000,000
Total	$ 456,935,000	$ 331,000,000	$ 379,324,000

No definition available.

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Amount of short term borrowing where a bank borrows, at the federal funds rate, from another bank.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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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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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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