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Note 16 - Income Taxes (Details Textual) - USD ($) $ in Thousands		12 Months Ended
	Jan. 01, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Unrecognized Tax Benefits, Income Tax Penalties Accrued		$ 0	$ 0
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent		21.00%	21.00%	21.00%	35.00%
Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect	$ 200
Domestic Tax Authority [Member]
Tax Credit Carryforward, Amount		$ 2,000
Domestic Tax Authority [Member] | Capital Loss Carryforward [Member]
Tax Credit Carryforward, Amount		$ 1,000
Tax Credit Carryforward, Expiration Year		2024
Domestic Tax Authority [Member] | Minimum [Member]
Tax Credit Carryforward, Expiration Year		2023
Domestic Tax Authority [Member] | Maximum [Member]
Tax Credit Carryforward, Expiration Year		2034
State and Local Jurisdiction [Member]
Tax Credit Carryforward, Amount		$ 4,200
Tax Credit Carryforward, Expiration Year		2021
Operating Loss Carryforwards, Total		$ 30,000
State and Local Jurisdiction [Member] | Minimum [Member]
Operating Loss Carryforwards, Expiration Year		2021
State and Local Jurisdiction [Member] | Maximum [Member]
Operating Loss Carryforwards, Expiration Year		2038
Foreign Tax Authority [Member]
Operating Loss Carryforwards, Total		$ 4,400
Foreign Tax Authority [Member] | Minimum [Member]
Operating Loss Carryforwards, Expiration Year		2023
Foreign Tax Authority [Member] | Maximum [Member]
Operating Loss Carryforwards, Expiration Year		2030

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
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Amount of increase (decrease) in accumulated other comprehensive income (AOCI) for reclassification to retained earnings of tax effect from remeasurement of deferred tax pursuant to Tax Cuts and Jobs Act.

+ References

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Amount of statutory penalties accrued for a tax position claimed or expected to be claimed by the entity, in its tax return.

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-Name Accounting Standards Codification
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