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Derivatives - Additional Information (Detail) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2017 USD ($) Derivatives | Mar. 31, 2016 USD ($) | Dec. 31, 2016 USD ($)
Risk participation Agreements [Line Items] |  |  |
HedgedItemsOfCashFlowHedge | $ 200,000 |  |
Risk Participation Agreements Purchased [Domain] |  |  |
Risk participation Agreements [Line Items] |  |  |
Number of interest rate swaps | Derivatives | 25 |  |
Risk Participation Agreements Sold [Domain] |  |  |
Risk participation Agreements [Line Items] |  |  |
Number of interest rate swaps | Derivatives | 8 |  |
Forward Contracts [Member] |  |  |
Risk participation Agreements [Line Items] |  |  |
Derivative, Net Hedge Ineffectiveness Gain (Loss) | $ 112 | $ 0 |
Derivative Liability, Cost Basis, Gross Asset | 5,800 |  |
Derivative Liability, Fair Value, Gross Asset | 6,000 |  |
Derivative Liability, Notional Amount, Gross Asset | 15,300 |  |
Forward Contracts [Member] | Designated as Hedging Instrument [Member] |  |  |
Risk participation Agreements [Line Items] |  |  |
Derivative, Fair Value, Net | 112 |  | $ 0
Derivative, Notional Amount | 17,000 |  | 0
Foreign Exchange [Member] |  |  |
Risk participation Agreements [Line Items] |  |  |
Derivative, Net Hedge Ineffectiveness Gain (Loss) | 2 | $ 3 |
Foreign Exchange Contract [Member] | Designated as Hedging Instrument [Member] |  |  |
Risk participation Agreements [Line Items] |  |  |
Derivative, Fair Value, Net | (38) |  | 8
Derivative, Notional Amount | 6,847 |  | 4,749
Derivative Liability, Cost Basis, Gross Asset | 6,800 |  | 4,700
Derivative Liability, Fair Value, Gross Asset | 6,800 |  | $ 4,700
Three Year Maturity [Member] | Designated as Hedging Instrument [Member] |  |  |
Risk participation Agreements [Line Items] |  |  |
Derivative, Notional Amount | 85,000 |  |
Four Year Maturity [Member] | Designated as Hedging Instrument [Member] |  |  |
Risk participation Agreements [Line Items] |  |  |
Derivative, Notional Amount | $ 115,000 |  |

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- Definition HedgedItemsOfCashFlowHedge + References No definition available. + Details
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- Definition [Line Items] for Risk participation Agreements [Table] + References No definition available. + Details
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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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- Definition Fair value of the assets less the liabilities of a derivative or group of derivatives. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13433-108611 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13495-108611 + Details
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- Definition Amount of gain (loss) from the ineffectiveness of the hedge. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (d)(1) -URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 25 -Section 50 -Paragraph 1 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986 + Details
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