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Noncash Share-based Compensation (Details) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2016	Sep. 30, 2015
Noncash Share-based Compensation (Narrative) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Forfeitures		4,086,000
Share-based Compensation Arrangement by Share-based Payment Award Accelerated Compensation Cost		$ 1,807,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized		900,000
Shares available for future grants	743,808	743,808
Unrecognized compensation cost related to share-based compensation	$ 39,758,000	$ 39,758,000
Weighted average period to recognize cost, in years		2 years 3 months 10 days
Share-based compensation arrangement by share-based payment, Minimum Employee Subscription rate		1.00%
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate	10.00%	10.00%
Share-based Compensation Arrangement by Share-based Payment Award, Discount from Market Price, Offering Date		15.00%	5.00%
Maximum Amount Contributable by employees under ESPP- Half yearly		$ 5,000
Maximum Amount Contributable By Employees Under ESPP- Annually		$ 10,000
Stock Issued During Period, Shares, Employee Stock Purchase Plans	41,845	65,693
ESPP contributions by Employees		$ 443,000
Restricted stock unit - market-based [Domain]
Noncash Share-based Compensation (Narrative) [Line Items]
Awards, other than options, granted in period	460,000	460,000
Weighted average grant date fair value, per share, of awards granted in period	$ 11.92	$ 11.92
RSUs
Noncash Share-based Compensation (Narrative) [Line Items]
Awards, other than options, granted in period	17,500	1,335,142
Weighted average grant date fair value, per share, of awards granted in period	$ 18.50	$ 11.50
MSUs
Noncash Share-based Compensation (Narrative) [Line Items]
Awards, other than options, granted in period		152,500
Weighted average grant date fair value, per share, of awards granted in period		$ 14.29
Employee Stock [Member]
Noncash Share-based Compensation (Narrative) [Line Items]
Shares reserved for issuance under Plan	383,310	383,310
2007 Equity Incentive Plan [Member]
Noncash Share-based Compensation (Narrative) [Line Items]
Shares reserved for issuance under Plan	9,968,000	9,968,000
Share-based Compensation Award, Tranche One [Member]
Noncash Share-based Compensation (Narrative) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Awards vesting upon Price Target	25.00%	25.00%
Share Price Target	$ 27	$ 27
Share-based Compensation Award, Tranche Two [Member]
Noncash Share-based Compensation (Narrative) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Awards vesting upon Price Target	25.00%	25.00%
Share Price Target	$ 33	$ 33
Share-based Compensation Award, Tranche Three [Member]
Noncash Share-based Compensation (Narrative) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Awards vesting upon Price Target	50.00%	50.00%
Share Price Target	$ 41	$ 41

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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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Additional share-based compensation cost recognized as a result of an occurrence of an event that accelerates its recognition.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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