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Income Tax - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions | 3 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Sep. 30, 2019 | Dec. 31, 2018 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Operating Loss Carryforwards [Line Items] |  |  |  |  |  |  |  |
Netherlands statutory income taxes rate |  |  | 25.00% | 25.00% | 25.00% |  |  |
Effect of the tax benefits on basic earnings per share |  |  | $ 0.14 | $ 0.15 | $ 0.13 |  |  |
Maximum percentage of tax reduction from tax holidays |  |  | 100.00% | 100.00% | 100.00% |  |  |
Income tax holiday expiration date |  |  | Dec. 31, 2028 |  |  |  |  |
Income tax benefit (expense) | $ 20 |  | $ 156 | $ 96 | $ 143 |  |  |
Legal inflationary index |  |  | (0.18%) |  |  |  |  |
Deferred tax benefit (expense) recorded as component of other comprehensive income (loss) |  |  | $ 6 | 7 |  |  |  |
Cumulative amount of distributable earnings |  | $ 2,863 | 3,628 | 2,863 |  |  |  |
Unrecognized tax benefits |  | 20 | 21 | 20 |  |  |  |
Reversal of uncertain tax positions |  | 310 |  |  |  |  |  |
Accrued interest and penalties related to uncertain tax positions |  | $ 1 |  | 1 |  | $ 1 | $ 1 | $ 27
Interest and penalties of unrecognized tax benefits |  |  | $ 6 | $ 5 |  |  |  |
Earliest Tax Year [Member] |  |  |  |  |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |  |  |  |  |
Open tax year |  |  | 1997 |  |  |  |  |
Latest Tax Year [Member] |  |  |  |  |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |  |  |  |  |
Open tax year |  |  | 2019 |  |  |  |  |
Maximum [Member] |  |  |  |  |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |  |  |  |  |
Accrued interest and penalties related to uncertain tax positions |  |  | $ 1 |  | $ 1 |  |  |

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