The number of awards granted during the period with performance vesting criteria.

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- Definition

Aggregate number of common shares reserved for future issuance based on the percentage of total shares of common stock outstanding.

+ References

No definition available.

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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=6415400&loc=d3e5070-113901

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- Definition

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).

+ 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 (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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).

+ 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 (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&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

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

+ References

No definition available.

+ 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=6415400&loc=d3e5070-113901

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

+ 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=6415400&loc=d3e5070-113901

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Stock Based Compensation - 2013 Stock Incentive Plan (Details)		1 Months Ended			12 Months Ended	52 Months Ended
	Jan. 01, 2018 shares	Jul. 31, 2015 shares	Apr. 30, 2015 shares	Jun. 30, 2014 shares	Dec. 31, 2017 $ / shares shares	Dec. 31, 2017 item shares	Dec. 31, 2016 shares	Sep. 30, 2013 shares
Stock-based compensation disclosures
Shares reserved for future awards					7,621,134	7,621,134	6,309,915
Employee and Consultant Options
Stock-based compensation disclosures
Options granted (in shares)					1,392,689
Restricted Stock
Stock-based compensation disclosures
Shares granted					480,000
Issued (in dollars per share) \| $ / shares					$ 28.05
2013 Plan
Stock-based compensation disclosures
Shares authorized								1,057,692
Increase to number of shares authorized		3,740,847	153,846	1,365,384
2013 Plan \| Outstanding stock options
Stock-based compensation disclosures
Vesting period					4 years
Expiration period					10 years
2013 Plan \| Performance based awards
Stock-based compensation disclosures
Number of awards with performance vesting criteria \| item						1
2015 Plan \| Subsequent Event
Stock-based compensation disclosures
Increase to number of shares authorized	1,801,017
2015 Employee Stock Purchase Plan
Stock-based compensation disclosures
Shares reserved for future awards					751,242	751,242	384,615
2015 Employee Stock Purchase Plan \| Subsequent Event
Stock-based compensation disclosures
Increase to number of shares authorized	450,254
Maximum \| 2013 Plan \| Consultant Stock Options
Stock-based compensation disclosures
Vesting period					4 years
Maximum \| 2015 Plan
Stock-based compensation disclosures
Shares reserved for future awards					2,923,076	2,923,076
Percent of shares outstanding reserved for future awards (as a percent)					4.00%
Maximum \| 2015 Employee Stock Purchase Plan
Stock-based compensation disclosures
Shares reserved for future awards					769,230	769,230
Percent of shares outstanding reserved for future awards (as a percent)					1.00%
Minimum \| 2013 Plan \| Consultant Stock Options
Stock-based compensation disclosures
Vesting period					1 year