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Restructuring and Other Charges - Narrative (Details) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2021 USD ($) | Jun. 30, 2020 USD ($) employee | Jun. 30, 2021 USD ($) | Jun. 30, 2020 USD ($)
Restructuring Cost and Reserve [Line Items] |  |  |  |
Restructuring and other charges | $ 5 | $ 105 | $ 14 | $ 144
Settlements | 3 | $ 64 | 6 | 64
Reversal of impairment charge due to reclassification of assets | employee |  | 7,000,000 |  |
Gain (loss) on sale of assets |  |  | 3 |
Pension benefits |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |
Settlements | $ 3 | $ 64 | $ 6 | 64
Layoff costs for the separation |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |
Restructuring and other charges |  | 54 |  | 76
U.S. Pension Plan Settlement Accounting |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |
Restructuring and other charges |  |  |  | 6
Other exit costs |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |
Restructuring and other charges |  | 2 |  | 5
Reversal of prior period programs |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |
Restructuring and other charges |  | 8 |  | 10
U.K. Pension Plan Settlement Accounting |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |
Restructuring and other charges |  | $ 64 |  | 64
Impairment of Property, Plant and Equipment |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |
Restructuring and other charges |  |  |  | 5
Sale of Assets |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |
Gain (loss) on sale of assets |  |  |  | $ 2

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