Income Taxes - Components of Provision for Income Taxes and Income before Provision for Income Taxes (Detail) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | 12 Months Ended | ||
|---|---|---|---|---|---|
Sep. 30, 2018 |
Sep. 30, 2017 |
Sep. 30, 2018 |
Sep. 30, 2017 |
Dec. 31, 2017 |
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| Income Tax Disclosure [Abstract] | |||||
| Income tax expense at the federal statutory rate | $ 6,125 | $ 8,920 | $ 17,599 | $ 24,713 | |
| State income tax expense, net of federal benefit | 1,462 | 993 | 3,974 | 2,734 | |
| Effect of foreign operations | (28) | 16 | (48) | 63 | |
| Windfall tax benefits, net related to stock-based compensation | (17) | 32 | (261) | (124) | |
| Change in valuation allowance | 162 | 38 | 284 | 154 | |
| Permanent items and other | 611 | 11 | 1,224 | 24 | |
| Provision for income taxes, amount | $ 8,315 | $ 10,010 | $ 22,772 | $ 27,564 | |
| Income tax expense at the federal statutory rate | 21.00% | 35.00% | 21.00% | 35.00% | 35.00% |
| State income tax expense, net of federal benefit | 5.00% | 3.90% | 4.70% | 3.90% | |
| Effect of foreign operations | (0.10%) | 0.10% | 0.00% | 0.10% | |
| Windfall tax benefits, net related to stock-based compensation | (0.10%) | 0.10% | (0.30%) | (0.20%) | |
| Change in valuation allowance | 0.60% | 0.20% | 0.30% | 0.20% | |
| Permanent items and other | 2.10% | 0.00% | 1.50% | 0.00% | |
| Provision for income taxes, rate | 28.50% | 39.30% | 27.20% | 39.00% | |
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- Definition Effective Income Tax Rate On Permanent Items And Other No definition available.
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- Definition Income Tax Reconciliation Permanent Items And Other No definition available.
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- Definition Amount of the difference in the grant date stock price and the vesting date stock price of employee and non-employee directors vesting of equity awards granted under the Company's 2013 Omnibus Equity Incentive Plan computed by applying the domestic federal statutory tax rates. No definition available.
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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://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to statutory income tax expense (benefit) outside of the country of domicile. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to equity-based compensation costs. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to state and local income tax expense (benefit), net of federal tax expense (benefit). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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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/disclosureRef
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- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to foreign income tax expense (benefit). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to state and local income tax expense (benefit). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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