v3.8.0.1

Note 10 - Commitments and Contingencies (Details Textual) $ in Thousands |  |  | 1 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | ---
Jun. 14, 2017 USD ($) a | Oct. 02, 2015 ft² $ / item | May 31, 2014 ft² | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($) | Dec. 31, 2011 ft²
Rental Rate Per Square Foot | $ / item |  | 2.05 |  |  |  |  |
Future Minimum Sublease Rentals, Sale Leaseback Transactions, Next Twelve Months |  |  |  | $ 300 |  |  |
Future Minimum Sublease Rentals, Sale Leaseback Transactions, within Two Years |  |  |  | 25 |  |  |
Operating Leases, Rent Expense, Net |  |  |  | $ 600 | $ 300 | $ 600 |
Redwood City, California [Member] |  |  |  |  |  |  |
Area of Operating Lease | ft² |  | 11,871 |  |  |  |  | 13,787
Lessee, Operating Lease, Term of Contract |  | 2 years 60 days |  |  |  |  |
Lease Extended Term [Member] |  |  |  |  |  |  |
Area of Operating Lease | ft² |  |  | 12,106 |  |  |  |
Lessee, Operating Lease, Renewal Term |  |  | 1 year 261 days |  |  |  |
Lease Agreement, Term |  |  | 3 years 180 days |  |  |  |
Executive Offices in Redwood City, CA [Member] | Metropolitan Life Insurance Company [Member] |  |  |  |  |  |  |
Lessee, Operating Lease, Renewal Term | 6 years |  |  |  |  |  |
Area of Real Estate Property | a | 25,893 |  |  |  |  |  |
Operating Lease, Annual Rent | $ 1,200 |  |  |  |  |  |
Lessee, Operating Lease, Term for Annual Rent Increase | 1 year |  |  |  |  |  |

X
- Definition Represents the number of square feet that are leased to the Company under a non-cancelable operating lease. + References No definition available. + Details
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X
- Definition Represents the term of an operating lease agreement. + References No definition available. + Details
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- Definition Term of lessee's annual rent increase under the operating lease. + References No definition available. + Details
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- Definition Per square rental rate of leased property. + References No definition available. + Details
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- Definition Amount of minimum sublease rentals for sale-leaseback transactions accounted for using the deposit method or as a financing to be received by the seller-lessee in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 40 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77914019&loc=d3e50824-112756 + Details
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- Definition Amount of minimum sublease rentals for sale-leaseback transactions accounted for using the deposit method or as a financing to be received by the seller-lessee in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 40 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77914019&loc=d3e50824-112756 + Details
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- Definition Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents 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 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980 + Details
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- Definition Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41499-112717 + Details
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