Noncash Share-based Compensation (Details)	3 Months Ended
Mar. 31, 2017 USD ($) $ / shares shares
Noncash Share-based Compensation (Narrative) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized	900,000
Unrecognized compensation cost related to share-based compensation \| $	$ 49,367,000
Weighted average period to recognize cost, in years	2 years 8 months
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%
Share-based Compensation Arrangement by Share-based Payment Award, Discount from Market Price, Offering Date	15.00%
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	50,927
ESPP contributions by Employees \| $	$ 426,000
RSUs
Noncash Share-based Compensation (Narrative) [Line Items]
Awards, other than options, granted in period	891,390
Weighted average grant date fair value, per share, of awards granted in period \| $ / shares	$ 21.38
MSUs
Noncash Share-based Compensation (Narrative) [Line Items]
Awards, other than options, granted in period	110,100
Weighted average grant date fair value, per share, of awards granted in period \| $ / shares	$ 26.99
Employee Stock [Member]
Noncash Share-based Compensation (Narrative) [Line Items]
Shares available for future grants	332,383
2007 Equity Incentive Plan [Member]
Noncash Share-based Compensation (Narrative) [Line Items]
Shares reserved for issuance under Plan	10,868,000
2017 Equity Incentive Plan [Member] [Member]
Noncash Share-based Compensation (Narrative) [Line Items]
Shares reserved for issuance under Plan	2,500,000
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%
Share Price Target \| $ / shares	$ 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%
Share Price Target \| $ / shares	$ 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%
Share Price Target \| $ / shares	$ 41

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Unrecognized cost of unvested share-based compensation awards.

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-Publisher FASB
-Name Accounting Standards Codification
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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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Discount rate from fair value on offering date that participants pay for shares.

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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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Number of additional shares authorized for issuance under an established share-based compensation plan.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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