Effective date for stock options plan.

No definition available.

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- Definition

Employee stock purchase plan number of purchase periods.

+ References

No definition available.

+ Details

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- Definition

Employee stock purchase plan offering period.

+ References

No definition available.

+ Details

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- Definition

Employee stock purchase plan purchase period.

+ References

No definition available.

+ Details

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- Definition

Increase in common stock reserved for future issuance.

+ References

No definition available.

+ Details

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Data Type:	xbrli:sharesItemType
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- Definition

Percentage of stock option exercise price of fair market value of common stock.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Percentage of voting power of all classes of stock.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Share based compensation arrangement by share based payment award options exercisable rate percentage.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- 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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Balance Type:	na
Period Type:	instant

- 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

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
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- Definition

General descriptive information regarding an arrangement under which employees and directors receive: (a) awards of equity shares, equity share options, or other equity instruments; or (b) the entity incurs liabilities to them: (1) in amounts based, at least in part, on the price of the entity's shares or other equity instruments; or (2) that require or may require settlement by issuance of the entity's shares. Such an arrangement is usually provided to employees and directors to compensate them, provide performance incentives to them, and to attract or retain their services. May also include pertinent information particular to a plan that is not elsewhere specified in the taxonomy.

+ 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)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901

+ Details

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Balance Type:	na
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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.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the 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
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of share instruments newly issued under a share-based compensation plan.

+ References

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
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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

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Purchase price of common stock expressed as a percentage of its fair value.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Stock Incentive Plans - Additional Information (Details)	1 Months Ended	9 Months Ended		12 Months Ended
	Oct. 31, 2016 shares	Sep. 30, 2017 Period $ / shares shares	Sep. 30, 2016 $ / shares	Dec. 31, 2016 shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options granted during the period		449,556		361,385
Shares available for future issuance		8,121,448		7,526,060
Estimated weighted-average grant date fair value of common stock underlying options granted \| $ / shares		$ 18.50	$ 5.78
2006 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option plan, description		Options under the Plan were granted for periods of up to ten years and at the fair value of the shares on the date of grant as determined by the board of directors.
Stock option vesting term		3 years
2006 Equity Incentive Plan \| First Anniversary of Grant
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option exercisable rate, Percentage		25.00%
2006 Equity Incentive Plan \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option, period for grant		10 years
2006 Equity Incentive Plan \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of voting power of all classes of stock		10.00%
2006 Equity Incentive Plan \| ISO \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option vesting term		5 years
2006 Equity Incentive Plan \| Other Options \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option vesting term		10 years
2016 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option plan, description		On the first day of each year beginning with 2017, the 2016 Plan authorizes an annual increase of the least of 3,865,000 shares, 5% of outstanding common stock on the last day of the immediately preceding fiscal year or an amount as determined by the Company's Board of Directors.
Effective date	Oct. 19, 2016
Options granted during the period	0
Shares available for future issuance	3,865,000	4,971,966
Percentage of outstanding common stock increased annually under the plan	5.00%
2016 Plan \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option, period for grant		10 years
2016 Plan \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of stock option exercise price of fair market value of common stock	100.00%
Employee Stock Purchase Program (“ESPP”)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Effective date	Oct. 19, 2016
Shares available for future issuance	483,031	709,993
Percentage of outstanding common stock increased annually under the plan	1.50%
Increase in shares available for future issuance	966,062
Offering period		12 months
Number of purchase period \| Period		2
Purchase period		6 months
Percentage of employee purchase shares of fair market value	85.00%
Common stock issued to employees		105,128
Employee Stock Purchase Program (“ESPP”) \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of payroll deductions of eligible compensation	15.00%