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Recent Accounting Pronouncements (Details) - USD ($) $ in Thousands | Mar. 31, 2019 | Jan. 01, 2019 | Dec. 31, 2018 | Jan. 31, 2017
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Recent Accounting Pronouncements |  |  |  |
Operating lease right-of-use assets, net | $ 1,378 |  |  |
Operating lease liability | 1,672 |  |  |
Share-based compensation liability | 402 |  | $ 3,018 |
Additional Paid in Capital | $ 183,834 |  | $ 180,862 |
Accounting Standards Update 2016-02 |  |  |  |
Recent Accounting Pronouncements |  |  |  |
Operating lease right-of-use assets, net |  |  |  | $ 2,300
Operating lease liability |  |  |  | $ 2,300
Accounting Standards Update 2016-02 | Adjustments |  |  |  |
Recent Accounting Pronouncements |  |  |  |
Operating lease right-of-use assets, net |  | $ 1,600 |  |
Operating lease liability |  | 1,900 |  |
Accounting Standards Update 2018-07 | Adjustments |  |  |  |
Recent Accounting Pronouncements |  |  |  |
Share-based compensation liability |  | (2,100) |  |
Additional Paid in Capital |  | $ 2,100 |  |

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- Definition Excess of issue price over par or stated value of the entity's capital stock and amounts received from other transactions involving the entity's stock or stockholders. Includes adjustments to additional paid in capital. Some examples of such adjustments include recording the issuance of debt with a beneficial conversion feature and certain tax consequences of equity instruments awarded to employees. Use this element for the aggregate amount of additional paid-in capital associated with common and preferred stock. For additional paid-in capital associated with only common stock, use the element additional paid in capital, common stock. For additional paid-in capital associated with only preferred stock, use the element additional paid in capital, preferred stock. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(30)(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements payable within one year (or the operating cycle, if longer). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.20) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Present value of lessee's discounted obligation for lease payments from operating lease. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977 + Details
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- Definition Amount of lessee's right to use underlying asset under operating lease. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977 + Details
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