Statement of Cash Flows Supplemental Disclosure - Supplemental Disclosures of Cash Flow Information (Detail) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017
Supplemental Cash Flow Information [Line Items]
Interest on deposits and borrowings	$ 10,016	$ 5,396
Income taxes	500	250
Supplemental schedule of noncash activities:
Transfers from loans to real estate owned and other repossessed assets	489	282
Transfers from loans to loans held for sale		27,921
Transfers from premises and equipment to other assets, held for sale		1,720
Accretion of securities held to maturity	$ 77	100
Ohio Legacy Corp. [Member]
Supplemental schedule of noncash activities:
Issuance of common stock		25,816
Net assets acquired excluding cash and cash equivalents		$ 36

Noncash activities, accretion of securities held to maturity.

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Noncash activities, transfers from premises and equipment to other assets held for sale.

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Supplemental cash flow information.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

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Amount of cash paid, after deduction of cash paid for capitalized interest, for interest. Includes, but is not limited to, payment to settle zero-coupon bond for accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.

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The fair value of stock issued in noncash financing activities.

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Value of loans and leases held in the entity's portfolio transferred to loans and leases held-for-sale in noncash transactions.

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