Employees contribution on earnings.

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Payment of underwriting discounts and commissions.

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Percentage of shares vested under performance target.

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Share based compensation arrangement by share based payment award equity instruments other than options granted in period fair value.

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The cash outflow for cost incurred directly with the issuance of an equity security.

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The cash inflow associated with the amount received from entity's first offering of stock to the public.

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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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Discount rate from fair value on offering date that participants pay for shares.

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Discount rate from fair value on purchase date that participants pay for shares.

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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.

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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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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Per share or per unit amount of equity securities issued.

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No definition available.

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

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Number of new stock issued during the period.

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Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

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Amount of stock repurchase plan authorized.

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Amount remaining of a stock repurchase plan authorized.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Stockholders' Equity - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Mar. 31, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Issuance of common stock, net of initial public offering costs				$ 217,796
Issuance of common stock for employee stock purchase plan (in shares)		283,644	272,836	249,494
Stock repurchase program, authorized amount		$ 100,000	$ 50,000	$ 45,000
Stock repurchase program, remaining authorized repurchase amount		$ 60,000
Number of shares repurchased		3,414,675	1,895,625	490,419
Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Term of stock options		4 years
Restricted Stock Unit
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total grant date fair value of awards granted		$ 41,700	$ 31,200
Performance-based restricted stock units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Term of stock options		3 years
ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available for grant		1,700,000
Minimum \| Performance-based restricted stock units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage range		0.00%
Maximum \| Performance-based restricted stock units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage range		200.00%
Nonemployee directors \| Maximum \| Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Contractual term		10 years
2009 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available for grant		6,671,436
Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options granted percentage of fair market value on offering date				85.00%
Stock options granted percentage of fair market value on purchase date				85.00%
Employee Stock Purchase Plan \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Employees contribution on earnings				1.00%
Employee Stock Purchase Plan \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Employees contribution on earnings				15.00%
IPO
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Initial public offering shares issued and sold (in shares)	15,000,000
Public offering share price	$ 16
Issuance of common stock, net of initial public offering costs	$ 240,000
Proceeds from issuance initial public offering, net of underwriting discounts and commissions	216,800
Underwriting discounts and commissions	16,800
Offering expenses	$ 5,600