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.

+ 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

+ Details

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- Definition

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

+ 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-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=96867065&loc=d3e5070-113901

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- Details

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- Details

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Equity Incentive Plans (Details 2) - shares shares in Thousands	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based awards outstanding	2,922
Stock-based awards available for grant as of December 31, 2017	1,099
2016 Employee Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based awards outstanding	213
2016 Director Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based awards outstanding	120
2005 Employee Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based awards outstanding	1,973
2005 Director Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based awards outstanding	368
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based awards outstanding	2,293	1,817
Stock Options [Member] \| 2016 Employee Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based awards outstanding	213
Stock Options [Member] \| 2016 Director Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based awards outstanding	60
Stock Options [Member] \| 2005 Employee Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based awards outstanding	1,652
Stock Options [Member] \| 2005 Director Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based awards outstanding	368
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based awards outstanding	629
Restricted Stock [Member] \| 2016 Employee Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based awards outstanding
Restricted Stock [Member] \| 2016 Director Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based awards outstanding	60
Restricted Stock [Member] \| 2005 Employee Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based awards outstanding	321
Restricted Stock [Member] \| 2005 Director Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based awards outstanding