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Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2015 | Sep. 30, 2015 | Jun. 30, 2015 | Mar. 31, 2015 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Income Tax [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Effective tax rate |  |  |  |  |  |  |  |  | 36.80% | 37.76% | 37.63% |
Effective income tax rate favorable impact of change in uncertain tax positions |  | $ 10,600 |  |  |  |  |  |  |  |  |  |
Effective tax rate excluding impact of tax settlement |  |  |  |  |  |  |  |  | 38.87% | 37.76% |  |
Adjustment to additional paid-in capital for excess tax benefits related to stock-based awards |  |  |  |  |  |  |  |  | $ 4,200 | $ 11,600 | $ 17,500 |
Net operating loss carryforwards for federal and state tax | $ 130,000 |  |  |  | $ 136,600 |  |  |  | 130,000 | 136,600 | 29,000 |
Uncertain tax position liability | 9,469 |  |  |  | 18,447 |  |  |  | 9,469 | 18,447 | 17,165 | $ 14,902
Unrecognized tax benefits that would impact effective tax rate | 9,500 |  |  |  |  |  |  |  | 9,500 |  |  |
Increase (decrease) in uncertain tax position |  |  |  |  |  |  |  |  | (9,000) | 1,200 |  |
Expected increase in uncertain tax position in the next twelve months | 2,200 |  |  |  |  |  |  |  | 2,200 |  |  |
Expected decrease in uncertain tax position in the next twelve months | 2,100 |  |  |  |  |  |  |  | 2,100 |  |  |
Income tax expense (benefit) | 49,919 | $ 44,272 | $ 51,601 | $ 43,411 | 51,581 | $ 55,640 | $ 52,889 | $ 43,928 | 189,203 | 204,038 | 191,413 |
Company's accrued liability for interest and penalties related to income tax liabilities | $ 1,400 |  |  |  | $ 9,300 |  |  |  | 1,400 | 9,300 |  |
Interest and Penalties [Member] |  |  |  |  |  |  |  |  |  |  |  |
Income Tax [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Income tax expense (benefit) |  |  |  |  |  |  |  |  | $ (7,900) | $ 600 | $ 300 |
Earliest Tax Year [Member] |  |  |  |  |  |  |  |  |  |  |  |
Income Tax [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Federal and state income tax examinations |  |  |  |  |  |  |  |  | 2012 |  |  |
Latest Tax Year [Member] |  |  |  |  |  |  |  |  |  |  |  |
Income Tax [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Federal and state income tax examinations |  |  |  |  |  |  |  |  | 2015 |  |  |
Minimum [Member] |  |  |  |  |  |  |  |  |  |  |  |
Income Tax [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Expiration period of operating loss carryforwards |  |  |  |  |  |  |  |  | 2019 |  |  |
Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |
Income Tax [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Expiration period of operating loss carryforwards |  |  |  |  |  |  |  |  | 2036 |  |  |

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