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Derivatives - Schedule of Changes in Fair Value of Derivative Assets and Liabilities (Detail) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2018 | Sep. 30, 2017
Derivative [Line Items] |  |  |  |
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net | $ 0 | $ (13) | $ 789 | $ (49)
Derivative, Net Hedge Ineffectiveness Gain (Loss) | 221 | 0 |  |
Interest Rate Contract [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, Net Hedge Ineffectiveness Gain (Loss) |  |  | (432) | 0
Interest Rate Swap [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative Instruments Designated As Hedging Instruments Interest Income | (193) | 35 | (424) | 420
Derivative, Net Hedge Ineffectiveness Gain (Loss) | 0 | 9 | 10 | 82
Forward Contracts [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, Net Hedge Ineffectiveness Gain (Loss) | 125 | 61 | 96 | (34)
Foreign Exchange [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, Net Hedge Ineffectiveness Gain (Loss) | $ 2 | $ 2 | $ 10 | $ 3

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- Definition Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4CC -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL109998890-113959 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959 + Details
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- Definition 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 No definition available. + Details
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- Definition Amount of gain (loss) from the ineffectiveness of the hedge. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 25 -Section 50 -Paragraph 1 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=109977999&loc=d3e76258-113986 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (d)(1) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959 + Details
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