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Accumulated Other Comprehensive Loss - Summary of Income Tax Benefit (Expense) to Component of Other Comprehensive Loss (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |
Accumulated net unrealized loss on translation of net investment in foreign operations | $ 7 | $ 7
Balance, beginning of year | 28 |
Balance, end of year | 27 | 28
Accumulated Net (Loss) Gain from Designated or Qualifying Cash Flow Hedges [Member] |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |
Balance, beginning of year | (14) | 23
Net unrealized loss (gain) | 12 | (36)
Reclassification of net loss to net income | (13) | (1)
Balance, end of year | (15) | (14)
Accumulated Net Unrealized Loss On Other Long Term Liabilities [Member] |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |
Balance, beginning of year | 35 | 21
Net unrealized loss (gain) | 1 | 15
Reclassification of net loss to net income | (1) | (1)
Balance, end of year | $ 35 | $ 35

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- Definition Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=121641772&loc=d3e637-108580 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=121641772&loc=d3e681-108580 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 45 -Paragraph 5A -URI http://asc.fasb.org/extlink&oid=116690757&loc=SL116692626-108610 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121641772&loc=SL7669646-108580 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=121641772&loc=SL7669686-108580 + Details
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