Stock-Based Compensation (Employee Stock Purchase Plan) (Details) shares in Thousands	12 Months Ended
Dec. 31, 2018 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum shares authorized	24,300
Shares available for future issuance	3,500
2012 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Offering periods	3 months
Purchase price (as a percent)	95.00%
Maximum shares authorized	2,500
Employee purchased shares	15
Shares available for future issuance	2,400

Employee Stock Purchase Plan (ESPP), Offering Period

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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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
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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

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

+ References

No definition available.

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

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-Name Accounting Standards Codification
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