Stock-based Compensation - Awards Granted Assumptions (Detail) - $ / shares |
12 Months Ended | ||
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Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2013 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Risk-free interest rate | 1.50% | 1.30% | 1.30% |
| Expected option life (in years) | 4 years 7 months 6 days | 4 years 4 months 13 days | 6 years |
| Forfeiture rate | 0.00% | 0.00% | 0.90% |
| Expected volatility | 42.30% | 42.80% | 48.50% |
| Weighted-average grant date fair value (in dollars per share) | $ 7.42 | $ 6.44 | $ 10.37 |
| Market Based Restricted Stock | |||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Risk-free interest rate | 1.10% | 1.10% | |
| Expected volatility | 38.70% | 43.60% | |
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- Definition Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Forfeiture Rate No definition available.
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- Definition The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The risk-free interest rate assumption that is used in valuing an option on its own shares. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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