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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions |  |  |  | 12 Months Ended
--- | --- | --- | --- | ---
Sep. 05, 2018 | Apr. 06, 2018 | Apr. 30, 2011 | Dec. 31, 2020
Disclosure of Income Taxes [Line Items] |  |  |  |
pre-tax income |  |  |  | $ 3,165
Prior year tax loss carryforwards value |  |  |  | $ 557
Increase in tax to be paid |  |  | $ 27 |
Income tax return 2012 [member] |  |  |  |
Disclosure of Income Taxes [Line Items] |  |  |  |
Income tax penalty imposed |  | $ 36 |  |
Income tax return 2011 [member] |  |  |  |
Disclosure of Income Taxes [Line Items] |  |  |  |
Income tax penalty imposed | $ 25 |  |  |

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