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Note 14 - Fair Value Measurements - Financial Assets and Liabilities Measured on a Recurring Basis at Fair Value (Details) - USD ($) $ in Thousands | Jun. 30, 2020 | Dec. 31, 2019
--- | --- | ---
Marketable securities - restricted |  | $ 2,296
Assets, Fair Value Disclosure |  | 2,321
Derivative liabilities | $ 6,689 |
Fuel Hedge [Member] |  |
Fuel hedge |  | 25
Derivative liabilities | 888 |
Interest Rate Swap [Member] |  |
Derivative liabilities | 5,801 | 3,825
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Marketable securities - restricted |  | 2,296
Assets, Fair Value Disclosure |  | 2,296
Derivative liabilities | 0 |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Fuel Hedge [Member] |  |
Fuel hedge |  | 0
Derivative liabilities | 0 |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Interest Rate Swap [Member] |  |
Derivative liabilities | 0 | 0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Marketable securities - restricted |  | 0
Assets, Fair Value Disclosure |  | 0
Derivative liabilities | 0 |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Fuel Hedge [Member] |  |
Fuel hedge |  | 0
Derivative liabilities | 0 |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Interest Rate Swap [Member] |  |
Derivative liabilities | 0 | 0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Marketable securities - restricted |  | 0
Assets, Fair Value Disclosure |  | 25
Derivative liabilities | 6,689 |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Fuel Hedge [Member] |  |
Fuel hedge |  | 25
Derivative liabilities | 888 |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Interest Rate Swap [Member] |  |
Derivative liabilities | $ 5,801 | $ 3,825

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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- Definition Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13433-108611 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details
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- Definition Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13433-108611 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313 + Details
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