Note 7 - Commitments and Contingencies (Details Textual) $ in Thousands	Dec. 31, 2019 USD ($)
Purchase Obligation, Due in Next Twelve Months	$ 16,700
Loss Contingency Accrual, Ending Balance	$ 0

Minimum amount of purchase arrangement maturing in the next fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

No definition available.

Name:	us-gaap_PurchaseObligationDueInNextTwelveMonths
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant