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Note 17 - Commitments and Contingencies (Details Textual) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Purchase Commitment, Remaining Minimum Amount Committed | $ 42.5 | $ 42.5
Arezzo Revenue Agency [Member] |  |
Loss Contingency, Estimate of Possible Loss | 12.0 |
Capital Addition Purchase Commitments [Member] |  |
Long-term Purchase Commitment, Amount | $ 2.1 | $ 2.8

X
- Definition The minimum amount the entity agreed to spend under the long-term purchase commitment. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Reflects the estimated amount of loss from the specified contingency as of the balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14435-108349 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 9 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14557-108349 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=121555522&loc=d3e12021-110248 + Details
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- Definition Minimum amount to be expended to satisfy the terms of arrangements in which the entity has agreed to expend funds to procure goods or services, excluding long-term purchase commitments or unconditional purchase obligations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(17)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(19)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(25)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |