Stock-based Compensation - Additional Information (Details) $ in Millions	6 Months Ended
Jun. 30, 2016 USD ($) shares
Incentive Plan 2005
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance	30,169,000
Number of shares available for issuance	8,054,000
Employee Stock Purchase Plan 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares available	2,400,000
Number of shares remaining	1,029,526
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unamortized compensation cost \| $	$ 79.0
Weighted average period of total unamortized cost (in years)	2 years 4 months 24 days
Market Performance Based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unamortized compensation cost \| $	$ 15.6
Weighted average period of total unamortized cost (in years)	1 year 7 months 6 days
Market Performance Based Restricted Stock Units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of granted market-performance based restricted stock units	2 years
Market Performance Based Restricted Stock Units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of granted market-performance based restricted stock units	3 years
Percentage of market-performance based restricted stock units eligible to vest over the vesting period	150.00%
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unamortized compensation cost \| $	$ 1.1
Weighted average period of total unamortized cost (in years)	4 months 24 days

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Aggregate number of common shares reserved for future issuance.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section 50
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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.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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