Derivative Financial Instruments - Impact of Derivatives on Consolidated Balance Sheet (Detail) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Derivatives, Fair Value [Line Items]
Total net derivatives	$ 30,000	$ 20,000
Interest rate swaps
Derivatives, Fair Value [Line Items]
Derivative instruments	1,403	812
Derivative Liabilities	(92)	(2,584)
Total net derivatives	1,311	(1,772)
Interest rate swaps \| Trading
Derivatives, Fair Value [Line Items]
Derivative instruments	0	182
Derivative Liabilities	(92)	0
Total net derivatives	(92)	182
Interest rate swaps \| Cash Flow \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative instruments	959	0
Derivative Liabilities	0	(2,584)
Total net derivatives	959	(2,584)
Interest rate swaps \| Fair Value \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative instruments	444	630
Derivative Liabilities	0	0
Total net derivatives	$ 444	$ 630

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 55
-Paragraph 10
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

+ References

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

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-Publisher FASB
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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.

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No definition available.

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