Income Taxes - Additional Information (Detail) - USD ($)  | 
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2015  | 
Sep. 30, 2014  | 
Sep. 30, 2015  | 
Sep. 30, 2014  | 
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| Income Tax Disclosure [Abstract] | ||||
| Provision (benefit) for income taxes for continuing operations | $ 10,569,000 | $ 5,368,000 | $ 27,722,000 | $ 20,078,000 | 
| Effective income tax rate | 43.09% | 19.76% | 41.55% | 31.20% | 
| Effective income tax rate, excluding bargain purchase gain and the merger and integration costs | 42.63% | 40.34% | ||
| Valuation allowance | $ 0 | $ 0 | ||
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- Definition Effective Income Tax Rate Reconciliation, Excluding Bargain Purchase Gain, Merger, And Integration Costs, Percent No definition available. 
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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- References No definition available. 
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| X | ||||||||||
- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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