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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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Maximum Percentage of Tax reduction from Tax holidays.

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Reversal of uncertain tax positions.

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Unrecognized tax benefits against existing net operating losses.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Per share amount effect of the income tax benefit resulting from the income tax holidays granted by taxing jurisdictions.

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Tax year that remains open to examination under enacted tax laws, in CCYY format.

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A segregation of retained earnings which is available for dividend distribution. Earnings not paid out as dividends but instead reinvested in the core business or used to pay off debt. Unappropriated profit is part of shareholder equity. Also called cumulative distributions or earned surplus or accumulated earnings or unappropriated profit.

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