| **Fair Values of Financial Instruments - Reconciliation of Beginning and Ending Balances of Recurring Fair Value Measurements using Significant Unobservable Level 3 Inputs (Detail) (USD $)In Thousands, unless otherwise specified** | 12 Months Ended |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-----------------|
||
| **Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]**                                                                                                                      |            |   |
| Purchases, issuances, and settlements                                                                                                                                                                                                  |            |    |
| Fair Value, Measurements, Recurring | Interest rate swap liability                                                                                                                                                                     |            |   |
| **Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]**                                                                                                                 |            |   |
| Beginning Balance                                                                                                                                                                                                                      |            | 7,797 |
| Included in net income                                                                                                                                                                                                                 |            | (863) |
| Transfers in/(out) of Level 3                                                                                                                                                                                                          |            | (6,934) |
| Ending balance                                                                                                                                                                                                                         |            |    |
| Fair Value, Measurements, Recurring | Available for Sale Securities                                                                                                                                                                    |            |   |
| **Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]**                                                                                                                      |            |   |
| Beginning Balance                                                                                                                                                                                                                      | 18,328          | 20,838 |
| Included in other comprehensive income                                                                                                                                                                                                 | 1,330           | (1,141) |
| Purchases, issuances, and settlements                                                                                                                                                                                                  | 7,590           |   |
| Transfers in/(out) of Level 3                                                                                                                                                                                                          | (16,434)        |   |
| Principal (payments)/additions                                                                                                                                                                                                         | (837)           | (1,369) |
| Ending balance                                                                                                                                                                                                                         | 9,977           | 18,328 |
| Fair Value, Measurements, Recurring | Interest rate swap asset                                                                                                                                                                         |            |   |
| **Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]**                                                                                                                      |            |   |
| Beginning Balance                                                                                                                                                                                                                      |            | 5,241 |
| Included in net income                                                                                                                                                                                                                 |            | (860) |
| Included in other comprehensive income                                                                                                                                                                                                 |            | 481 |
| Transfers in/(out) of Level 3                                                                                                                                                                                                          |            | (4,862) |
| Ending balance                                                                                                                                                                                                                         |            |    |
| Fair Value, Measurements, Recurring | Interest rate cap                                                                                                                                                                                |            |   |
| **Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]**                                                                                                                      |            |   |
| Beginning Balance                                                                                                                                                                                                                      |            | 424 |
| Included in other comprehensive income                                                                                                                                                                                                 |            | (15) |
| Transfers in/(out) of Level 3                                                                                                                                                                                                          |            | (409) |
| Ending balance                                                                                                                                                                                                                         |            |    |

| X                                                                                                                                                                                                                                                                                                                                                                                              |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Principal Payments
+ References
No definition available.
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| X                                                                                                                                                                                                                                |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                                                                                     |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of gain (loss) recognized in other comprehensive income (loss) for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1a) -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of purchases, (sales), issuances and (settlements) of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph c -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258
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| X                                                                                                                                                                                                                                                                                                                                                                                                        |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of transfer of financial instrument classified as an asset into (out of) level 3 of the fair value hierarchy.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258
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| X                                                                                                                                                                                                                                                                                                                                                                                                                 |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of transfers of financial instrument classified as a liability into (out of) level 3 of the fair value hierarchy.
+ References
No definition available.
+ Details**Name:**us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityTransfersNet**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**credit**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258
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