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Note 17 - Commitments and Contingencies - Personal Injury Liability Activity (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Balance, Current | $ 187 | $ 177 |
Personal Injury [Member] |  |  |
Balance | 270 | 265 | $ 271
Current year accruals | 93 | 72 | 78
Changes in estimates for prior years | 48 | (3) | (11)
Payments | (86) | (64) | (73)
Balance | 325 | 270 | 265
Balance, Current | $ 64 | $ 60 | $ 63

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- Definition Amount of expense (reversal of expense) which increases (decreases) the accrual for loss contingencies from revisions in estimates to existing obligations. + References No definition available. + Details
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- Definition Amount of loss contingency liability. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349 + Details
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- Definition Amount of loss contingency liability expected to be resolved within one year or the normal operating cycle, if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349 + Details
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- Definition Amount of cash outflow reducing loss contingency liability. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349 + Details
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- Definition Amount charged against operating income increasing loss contingency liability, after adjustments to reduce previously estimated charges. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349 + Details
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- Details
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