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Ownership Percentages and Carrying Value Principal Equity Method Investments (Parenthetical) (Detail) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020
Schedule of Equity Method Investments [Line Items] |  |
Unrealized Gains on Equity Securities | $ 63 | $ 65
Sales to equity method investees | $ 65 | $ 104
Equity method investment difference between carrying amount and underlying Equity accounting treatment weighted average amortization period | 8 years |
LG Magna e-Powertrain Co., Ltd. [Member] |  |
Schedule of Equity Method Investments [Line Items] |  |
Carrying value of equity method investments | $ 188 |

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- Definition Amount of unrealized gain (loss) on investment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585 + Details
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