Note 4 - Lease Commitments - Lease Costs (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019 USD ($)	Sep. 30, 2019 USD ($)
Rent expense, operating leases	$ 542	$ 1,533
Leased furniture, fixtures and office equipment depreciation expense, finance lease	73	170
Interest expense, finance lease	10	32
Rent expense, short-term leases	85	342
Total lease costs	$ 710	$ 2,077
Weighted average remaining lease-term (in years), operating leases (Year)	6 years	6 years
Weighted average remaining lease-term (in years), finance lease (Year)	6 years 73 days	6 years 73 days
Weighted average discount rate, operating leases	5.00%	5.00%
Weighted average discount rate, finance lease	5.00%	5.00%

Amount of interest expense on finance lease liability.

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Amount of amortization expense attributable to right-of-use asset from finance lease.

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Weighted average discount rate for finance lease calculated at point in time.

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Weighted average remaining lease term for finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of lease cost recognized by lessee for lease contract.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of short-term lease cost, excluding expense for lease with term of one month or less.

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