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Other Expense, Net - Other Expense, Net (Parenthetical) (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Components of Other Expense (Income), Net [Line Items] |  |
Restructuring | $ 21 |
Restructuring charges, after tax | 21 |
Unrealized gain on investment revaluation | 65 | $ 31
Impairment of assets | 435 | 727
Asset impairment charges after tax | 57 |
Net (gains) losses on investment | (32) | 6
Loss on investments, after tax |  | 5
Proceeds from sale of investments |  | 231
Proceeds on the sale of business |  | 1,230
Gain on the sale of business |  | 524
Gain on the sale of business, after tax |  | 447
Private Equity Investments [Member] |  |
Components of Other Expense (Income), Net [Line Items] |  |
Unrealized gain on investment revaluation | 34 | 17
Unrealized gain on investment revaluation, after tax | 29 | 15
Non-cash impairment charge on private equity investment | 2 |
Non-cash impairment charge on private equity investment, after tax | 2 |
Lyft [Member] | Private Equity Investments [Member] |  |
Components of Other Expense (Income), Net [Line Items] |  |
Net (gains) losses on investment |  | 23
Loss on investments, after tax |  | $ 20
Number of shares sold of (investment in) Lyft, Inc. |  | 5,400,000
Proceeds from sale of investments |  | $ 231
Power & Vision [Member] |  |
Components of Other Expense (Income), Net [Line Items] |  |
Restructuring |  |
Power & Vision [Member] | Electronic Operations [Member] |  |
Components of Other Expense (Income), Net [Line Items] |  |
Impairment of assets |  | 27
Asset impairment charges after tax |  | 20
Body Exteriors & Structures [Member] |  |
Components of Other Expense (Income), Net [Line Items] |  |
Restructuring | $ 21 | 31
Restructuring charges, after tax |  | $ 31

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