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Stock-Based Compensation (Details) | 12 Months Ended
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Dec. 31, 2017 USD ($) shares
Employee [Member] | Employee Equity and Incentive Plan 2017 [Member] |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Number of shares authorized | 5,500,000
Director [Member] | Non-Employee Director Equity Plan 2014 [Member] |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Number of shares authorized | 600,000
Maximum aggregate grant date fair market value of awards per director for each calendar year | $ | $ 750,000

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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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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