Share-based compensation arrangement by share-based payment award, additional number of shares available for grant.

No definition available.

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- Definition

The maximum annual increase in the number of shares reserved under the plan as a proportion of outstanding common stock.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award shares issued in period fair value.

+ References

No definition available.

+ Details

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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

The cash inflow associated with the amount received from the stock plan during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3255-108585

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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 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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=109197908&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

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Details

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Stock-Based Compensation - Additional Information (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Feb. 20, 2018	Jan. 01, 2018	Jan. 01, 2017
2018 Equity Inducement Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Initial reserves of common stock					1,100,000
2016 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of outstanding share of common stock			4.00%
Additional number of shares available for issuance						666,807	537,233
Common stock available for future issuance	84,521		84,521
2016 Equity Incentive Plan and 2018 Equity Inducement Plan \| Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option to purchase an aggregate of common stock shares	255,800	735,600	1,288,900	1,753,300
Stock options to purchase common stock aggregate fair value	$ 1,700,000	$ 1,700,000	$ 7,100,000	$ 6,600,000
2016 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option to purchase an aggregate of common stock shares	24,977	20,990	55,914	39,174
Aggregate cash proceeds from sale of shares	$ 129,000	$ 53,000	$ 207,000	$ 131,000