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Note 14 - Income Taxes - Expiration of Tax Net Operating Losses and Tax Credits Available (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Domestic Tax Authority [Member]
Tax Credits	$ 23,002
Domestic Tax Authority [Member] | Tax Years 2022 to 2032 [Member]
Tax Credits	0
Domestic Tax Authority [Member] | Tax Years 2033 to 2038 [Member]
Tax Credits	22,220
Domestic Tax Authority [Member] | Tax Years 2039 to 2043 [Member]
Tax Credits	782
State and Local Jurisdiction [Member]
Tax Credits	32,177
State Net Operating Losses	1,860
State and Local Jurisdiction [Member] | Tax Years 2022 to 2032 [Member]
Tax Credits	0
State Net Operating Losses	1,833
State and Local Jurisdiction [Member] | Tax Years 2033 to 2038 [Member]
Tax Credits	2,643
State Net Operating Losses	27
State and Local Jurisdiction [Member] | Tax Years 2039 to 2043 [Member]
Tax Credits	29,534
State Net Operating Losses	$ 0

X

- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32559-109319

+ Details

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X

- Definition

The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32559-109319

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