Note 8 - Lease Obligations - Lease Obligations (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Amortization of right-of-use assets	$ 915	$ 968	$ 1,922	$ 2,005
Interest on lease liabilities	159	278	333	525
Operating lease cost	5,853	7,445	11,764	14,047
Variable lease cost	28	156	91	314
Total lease cost	6,955	8,847	14,110	16,891
Operating cash flows from finance leases	915	968	1,922	205
Operating cash flows from operating leases	4,757	7,601	9,532	14,361
Financing cash flows from finance leases	159	275	333	525
Right-of-use assets obtained in exchange for new operating lease liabilities	$ 2,305	$ 2,176	$ 2,530	$ 2,637
Weighted-average remaining lease term—finance leases (Year)	1 year 3 months 18 days		1 year 3 months 18 days
Weighted-average remaining lease term—operating leases (Year)	2 years 4 months 24 days		2 years 4 months 24 days
Weighted-average discount rate—finance leases	4.30%		4.30%
Weighted-average discount rate—operating leases	6.00%		6.00%

The amount of cash outflow for payments of finance lease under financing activities.

No definition available.

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- Definition

Amount of interest expense on finance lease liability.

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- Definition

Amount of interest paid on finance lease liability.

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- Definition

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

+ References

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

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- Definition

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.

+ References

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- Definition

Amount of lease cost recognized by lessee for lease contract.

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- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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

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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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- Definition

Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

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- Definition

Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

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