Stock Compensation - Additional Information (Detail) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2016 |
Sep. 30, 2015 |
Sep. 30, 2016 |
Sep. 30, 2015 |
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| Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] | ||||
| Share-based compensation expense | $ 6.2 | $ 4.7 | $ 17.1 | $ 13.5 |
| Unrecognized compensation cost related to nonvested common shares | $ 62.5 | $ 62.5 | ||
| Weighted average period for recognition of cost | 2 years 2 months 12 days | |||
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- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Unrecognized cost of unvested share-based compensation awards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, 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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