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Note 7 - Revenue 2 (Details Textual) $ in Millions | Dec. 31, 2020 USD ($)
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Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01 | Fixed-price Contract [Member] |
Revenue, Remaining Performance Obligation, Amount | $ 493
Revenue, Remaining Performance Obligation, Percentage | 78.00%
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period (Year) | 2 years
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01 | Contracts with Price Reopeners [Member] |
Revenue, Remaining Performance Obligation, Amount | $ 237
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period (Year) | 1 year

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- Definition Amount of transaction price allocated to performance obligation that has not been recognized as revenue. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 13 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130556-203045 + Details
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- Definition Period in which remaining performance obligation is expected to be recognized as revenue, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 13 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130556-203045 + Details
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- Definition Percentage of remaining performance obligation to total remaining performance obligation not recognized as revenue. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 13 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130556-203045 + Details
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