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Stockholders' Equity - Options Outstanding and Exercisable (Details) | 12 Months Ended
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Dec. 31, 2017 $ / shares shares
OPTIONS OUTSTANDING |
Number of Shares Outstanding (in shares) | shares | 248,512
Weighted Average Remaining Contractual Life (in years) | 7 years 9 months 18 days
Weighted Average Exercise Price (in dollars per share) | $ 5.76
OPTIONS EXERCISABLE |
Number of Shares Exercisable (in shares) | shares | 110,476
Weighted Average Remaining Contractual Life (in years) | 6 years 1 month 6 days
Weighted Average Exercise Price (in dollars per share) | $ 8.63
Exercise price, range one |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Range of Exercise Prices, lower limit (in dollars per share) | 2.30
Range of Exercise Prices, upper limit (in dollars per share) | $ 3.25
OPTIONS OUTSTANDING |
Number of Shares Outstanding (in shares) | shares | 59,558
Weighted Average Remaining Contractual Life (in years) | 9 years 1 month 6 days
Weighted Average Exercise Price (in dollars per share) | $ 3.04
OPTIONS EXERCISABLE |
Number of Shares Exercisable (in shares) | shares | 2,000
Weighted Average Remaining Contractual Life (in years) | 4 years 10 months 24 days
Weighted Average Exercise Price (in dollars per share) | $ 2.45
Exercise price, range two |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Range of Exercise Prices, lower limit (in dollars per share) | 3.26
Range of Exercise Prices, upper limit (in dollars per share) | $ 4.00
OPTIONS OUTSTANDING |
Number of Shares Outstanding (in shares) | shares | 74,165
Weighted Average Remaining Contractual Life (in years) | 9 years 2 months 12 days
Weighted Average Exercise Price (in dollars per share) | $ 3.43
OPTIONS EXERCISABLE |
Number of Shares Exercisable (in shares) | shares | 0
Weighted Average Remaining Contractual Life (in years) | 9 years 2 months 12 days
Weighted Average Exercise Price (in dollars per share) | $ 3.43
Exercise price, range three |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Range of Exercise Prices, lower limit (in dollars per share) | 4.01
Range of Exercise Prices, upper limit (in dollars per share) | $ 5.50
OPTIONS OUTSTANDING |
Number of Shares Outstanding (in shares) | shares | 51,919
Weighted Average Remaining Contractual Life (in years) | 6 years 7 months 6 days
Weighted Average Exercise Price (in dollars per share) | $ 4.96
OPTIONS EXERCISABLE |
Number of Shares Exercisable (in shares) | shares | 50,461
Weighted Average Remaining Contractual Life (in years) | 6 years 7 months 6 days
Weighted Average Exercise Price (in dollars per share) | $ 4.94
Exercise price, range four |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Range of Exercise Prices, lower limit (in dollars per share) | 5.51
Range of Exercise Prices, upper limit (in dollars per share) | $ 20.00
OPTIONS OUTSTANDING |
Number of Shares Outstanding (in shares) | shares | 62,870
Weighted Average Remaining Contractual Life (in years) | 6 years
Weighted Average Exercise Price (in dollars per share) | $ 11.75
OPTIONS EXERCISABLE |
Number of Shares Exercisable (in shares) | shares | 58,015
Weighted Average Remaining Contractual Life (in years) | 5 years 9 months 18 days
Weighted Average Exercise Price (in dollars per share) | $ 12.05

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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. + Details
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- Definition The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range. + 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 (g) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied. + 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 (c)(iii) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices. + 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 (c)(1)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range. + 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 (g) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + 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 + Details
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- Definition Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding. + 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 (c)(1)(iii) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices. + 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 (c)(1)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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