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.

No definition available.

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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 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

Number of options outstanding, including both vested and non-vested options.

+ 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

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

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- Details

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Stock-Based Compensation - Shares Reserved for Future Issuance (Details) - shares shares in Thousands	Jan. 01, 2019	Dec. 31, 2018
Common Stock Reserved for Future Issuance
Total		12,127
2001 Stock Plan
Common Stock Reserved for Future Issuance
Stock options issued and outstanding (in shares)		510
2011 Stock Plan
Common Stock Reserved for Future Issuance
Stock options issued and outstanding (in shares)		1,540
2015 Stock Plan
Common Stock Reserved for Future Issuance
Stock options issued and outstanding (in shares)		4,789
Authorized for future stock awards or option grants (in shares)		4,226
Total	11,300
Employee Stock Purchase Plan 2015
Common Stock Reserved for Future Issuance
Authorized for future stock awards or option grants (in shares)		1,062
Total	1,800