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Income Taxes And Tax-Related Items Reconciliation of the Beginning and Ending Amounts of Unrecognized Tax Benefits (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Income Tax Disclosure [Abstract] |  |  |
Balance at January 1 | $ 19 | $ 17 | $ 14
Increase as a result of tax positions taken during a prior period | 1 | 1 | 4
Increase as a result of tax positions taken during a current period | 3 | 2 | 0
Decreases related to settlements with tax authorities | (3) | (1) | (1)
Reduction as a result of expiration of statute of limitations | (2) | 0 | 0
Balance at December 31 | $ 18 | $ 19 | $ 17

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- Definition Amount of unrecognized tax benefits. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 10B -URI http://asc.fasb.org/extlink&oid=123427490&loc=SL37586934-109318 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121826272&loc=SL6600010-109319 + Details
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=121826272&loc=SL6600010-109319 + Details
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