Stock-Based Compensation - Additional information (Details) - shares	6 Months Ended
Jun. 30, 2018	May 22, 2013
2010 Equity Incentive Plan \| Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years
Award expiration period	10 years
2010 Equity Incentive Plan \| Restricted Stock Units (RSUs) \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	1 year
2010 Equity Incentive Plan \| Restricted Stock Units (RSUs) \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years
2010 Equity Incentive Plan \| Market-based share unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum MSU payout percentage	200.00%
Award vesting period	3 years
2013 Employee Stock Purchase Plan \| Employee stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized		650,000
Number of shares available for grant	1,059,213
Discount from market price, offering date	85.00%
Maximum number of shares per employee	1,500
Maximum employee subscription rate	0.00%
2013 Employee Stock Purchase Plan \| Employee stock \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Offering period	6 months
2013 Employee Stock Purchase Plan \| Employee stock \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Offering period	27 months
2013 Employee Stock Purchase Plan Amended and Restated \| Employee stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	1,750,000

Share Based Compensation Arrangement by Share-based Payment Award, Offering Period

No definition available.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

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.

+ References

No definition available.

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- Definition

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

+ References

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- Definition

The highest quantity of shares an employee can purchase under the plan per period.

+ References

+ Details

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- Definition

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).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

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- Definition

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.

+ References

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- Definition

Percentage of vesting of share-based compensation awards.

+ References

+ Details

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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