| **Derivatives - Additional Information (Detail) $ in Thousands**                                       | 12 Months Ended |
|--------------------------------------------------------------------------------------------------------|-----------------|
||
| **Derivative [Line Items]**                                                                            |            |   |   |
| Number of participation agreements for interest rate swaps, participant | Derivative                   | 31              |   |   |
| Number of participation agreements for interest rate swaps, lead bank | Derivative                     | 10              |   |   |
| Derivative, Gain (Loss) on Derivative, Net                                                             | $ 787           | $ (473) | $ 219 |
| Interest Rate Swap [Member] | Cash Flow Hedging [Member]                                               |            |   |   |
| **Derivative [Line Items]**                                                                            |            |   |   |
| Derivative, notional amount                                                                            | 65,000          |   |   |
| Collateral Already Posted, Aggregate Fair Value                                                        | 65,000          |   |   |
| Interest Rate Swap [Member] | Designated as Hedging Instrument [Member]                                |            |   |   |
| **Derivative [Line Items]**                                                                            |            |   |   |
| Derivative, notional amount                                                                            | 65,000          | 150,000 |   |
| Interest Rate Swap [Member] | Interest Income [Member] | Designated as Hedging Instrument [Member]     |            |   |   |
| **Derivative [Line Items]**                                                                            |            |   |   |
| Derivative, Gain (Loss) on Derivative, Net                                                             | (590)           | 452 | 1,627 |
| Interest Rate Swap [Member] | Other Income [Member] | Designated as Hedging Instrument [Member]        |            |   |   |
| **Derivative [Line Items]**                                                                            |            |   |   |
| Derivative, Gain (Loss) on Derivative, Net                                                             | 10              | 119 | 70 |
| Foreign Exchange Contract [Member] | Designated as Hedging Instrument [Member]                         |            |   |   |
| **Derivative [Line Items]**                                                                            |            |   |   |
| Derivative, notional amount                                                                            | 1,927           | 10,077 |   |
| Derivative, Underlying Asset Carrying Value                                                            | 1,900           | 10,000 |   |
| Derivative Liability, Fair Value, Gross Asset                                                          | 1,900           | 10,100 |   |
| Foreign Exchange Contract [Member] | Other Income [Member] | Designated as Hedging Instrument [Member] |            |   |   |
| **Derivative [Line Items]**                                                                            |            |   |   |
| Derivative, Gain (Loss) on Derivative, Net                                                             | 15              | 4 | (5) |
| Forward Contracts [Member] | Designated as Hedging Instrument [Member]                                 |            |   |   |
| **Derivative [Line Items]**                                                                            |            |   |   |
| Derivative, notional amount                                                                            | 15,000          | 17,000 |   |
| Derivative, Underlying Asset Carrying Value                                                            | 6,900           | 14,300 |   |
| Derivative Liability, Fair Value, Gross Asset                                                          | 7,600           | 14,700 |   |
| Derivative Liability, Notional Amount                                                                  | 9,900           | 13,800 |   |
| Forward Contracts [Member] | Other Income [Member] | Designated as Hedging Instrument [Member]         |            |   |   |
| **Derivative [Line Items]**                                                                            |            |   |   |
| Derivative, Gain (Loss) on Derivative, Net                                                             | $ (189)         | $ (19) | $ 0 |
| Four Year [Member] | Interest Rate Swap [Member] | Cash Flow Hedging [Member]                          |            |   |   |
| **Derivative [Line Items]**                                                                            |            |   |   |
| Derivative, Term of Contract                                                                           | 4 years         |   |   |

| X                                                                                                                                                                                                                                                                     |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Derivative, Underlying Asset Carrying Value
+ References
No definition available.
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| X                                                                                                                                                                                                                                                             |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Derivative, Underlying Asset Fair Value
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                           |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of Participation Agreements, Interest Rate Derivatives Held as a Participant
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.
+ References
Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4H -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624258-113959
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.
+ References
Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Nominal or face amount used to calculate payments on the derivative liability.
+ References
Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959
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| X                                                                                                                                                                                                                                                                                                                                                                                                           |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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.
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| X                                                                                                                                                                                                                                                                                                                                                                                              |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of interest rate derivative instruments held by the entity at the reporting date.
+ References
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| X                                                                                                                                                           |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                                    |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                  |
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| X                                                                                                                                                           |
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| X                                                                                                                               |
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