v3.8.0.1

Note 7 - Long-term Debt (Details Textual) $ / shares in Units, $ in Thousands |  |  |  | 1 Months Ended | 6 Months Ended | 12 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Mar. 02, 2017 USD ($) | Sep. 18, 2015 $ / shares shares | Dec. 16, 2013 USD ($) $ / shares shares | Sep. 30, 2016 $ / shares shares | Dec. 31, 2013 $ / shares shares | Jun. 30, 2016 $ / shares | Mar. 01, 2020 | Mar. 01, 2019 | Mar. 01, 2018 | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($) shares | Oct. 01, 2017 USD ($) | Sep. 17, 2015 $ / shares | Dec. 31, 2014 USD ($) | Sep. 24, 2014 USD ($) | Jun. 16, 2014 USD ($)
Repayments of Long-term Debt |  |  |  |  |  |  |  |  |  | $ 3,514 |  | $ 4,534 |  |  |  |  |
Common Stock Warrants Exercised | shares |  |  |  |  |  |  |  |  |  |  |  | 847,058 |  |  |  |  |
Fair Value of Contingent Put Option, Liability |  |  |  |  |  |  |  |  |  | 207 | 124 |  |  |  |  |  |
Interest Expense |  |  |  |  |  |  |  |  |  | 3,316 | $ 2,770 | $ 2,977 |  |  |  |  |
Hercules Warrants [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Warrants Exercised | shares |  | 176,730 | 176,730 | 176,730 | 176,730 |  |  |  |  |  |  |  |  |  |  |  |
Class of Warrant or Right, Exercise Price of Warrants or Rights | $ / shares |  | $ 3.88 | $ 6.79 | $ 3.07 | $ 9.67 |  |  |  |  |  |  |  |  | $ 6.79 |  |  |
Investment Warrants, Exercise Price | $ / shares |  |  |  | $ 3.07 | $ 6.79 | $ 3.88 |  |  |  |  |  |  |  |  |  |  |
Amended and Restated Loan and Security Agreement [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity |  |  | $ 40,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of Tranches for Loan and Security Agreement |  |  | 3 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Fair Value Disclosure |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 24,900 |  |
Long-term Debt Maturities Balloon Payments |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,700 |  |  |  |
Debt Instrument, Variable Rate Threshold | 9.55% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Percentage Used to Calculate Variable Rate | 3.50% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Final Payment, Percentage of Aggregate Principal Amount | 6.50% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amended and Restated Loan and Security Agreement [Member] | Prime Rate [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage |  |  |  |  |  |  |  |  |  |  | 9.55% |  |  |  |  |  |
Amended and Restated Loan and Security Agreement [Member] | First Tranche [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Face Amount | $ 20,500 |  | $ 15,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repayments of Long-term Debt |  |  | 8,600 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amended and Restated Loan and Security Agreement [Member] | Second Tranche [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Face Amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 10,000
Amended and Restated Loan and Security Agreement [Member] | Third Tranche [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 15,000 |
Hercules Loan and Security Agreement [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Additional Default Interest Rate | 5.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fair Value of Contingent Put Option, Liability |  |  | $ 32 |  |  |  |  |  |  | 200 | $ 100 |  |  |  |  |  |
Long-term Line of Credit |  |  |  |  |  |  |  |  |  | 19,100 | 21,500 |  |  |  |  |  |
Interest Expense |  |  |  |  |  |  |  |  |  | $ 3,300 | $ 2,800 | $ 3,000 |  |  |  |  |
Hercules Loan and Security Agreement [Member] | Scenario, Forecast [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Prepayment Charge of Term Loan Percentage |  |  |  |  |  |  | 1.00% | 2.00% | 3.00% |  |  |  |  |  |  |  |

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- Definition The final payment, expressed as a percentage of aggregate principal amount, under a debt agreement. + References No definition available. + Details
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- Definition The percentage that is used to determine the debt instruments variable rate. + References No definition available. + Details
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- Definition Represents the percentage of variable rate threshold used to determine the interest rate under the debt agreement. If the reference rate is above this percentage threshold, the interest rate equals to the minimum stated rate plus the difference between the reference rate and the threshold. If the reference rate is below this percentage threshold, the interest rate equals to the minimum stated rate. + References No definition available. + Details
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- Definition Exercise price of the warrants. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column A + Details
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- Definition Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium. + 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 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399 + Details
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- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. + 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(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. + 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 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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