Income Taxes - Provision for Income Taxes for Continuing Operations - (Benefit) Expense (Detail) - USD ($) $ in Thousands  | 
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2016  | 
Dec. 31, 2015  | 
Dec. 31, 2014  | 
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| Current: | |||
| Federal | $ 43,655 | $ 36,241 | $ 36,874 | 
| State | 3,766 | 6,414 | 5,771 | 
| Total current | 47,421 | 42,655 | 42,645 | 
| Deferred | 13,275 | 14,410 | 20,523 | 
| Total provision for income taxes for continuing operations - (benefit) expense | $ 60,696 | $ 57,065 | $ 63,168 | 
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- Definition Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations. No definition available. 
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- Definition Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Amount of current income tax expense (benefit) pertaining to taxable income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- References No definition available. 
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- Definition Amount of current state and local tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- 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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