Income Taxes - Summary of Changes in Liability Related to Unrecognized Tax Benefits (Parenthetical) (Detail) - USD ($) $ in Millions |
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
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| Schedule Of Unrecognized Tax Benefits [Line Items] | ||||
| Accrued interest and penalties | $ 0.6 | $ 0.8 | $ 1.1 | $ 1.2 |
| State and Local Jurisdiction [Member] | ||||
| Schedule Of Unrecognized Tax Benefits [Line Items] | ||||
| Net operating losses | $ 0.1 | $ 0.3 | $ 0.6 |
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- Definition Schedule of unrecognized tax benefits. No definition available.
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- Definition The amount of estimated penalties and interest accrued as of the balance sheet date arising from income tax examinations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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