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Accumulated Other Comprehensive Loss - Changes (Detail) - USD ($) $ in Millions		12 Months Ended
	Jan. 01, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Mar. 31, 2016
AOCI roll forward
Beginning balance	$ 6,042	$ 6,042	$ 5,320	$ 5,367
Other comprehensive income (loss), net of tax		(90)	88	47
Ending balance		6,276	6,042	5,320
Accounting Standards Update 2018-02 [Member]
AOCI roll forward
Adoption of new accounting standard	5
Accumulated Other Comprehensive Loss [Member]
AOCI roll forward
Beginning balance	8	8	(80)	(127)
Other comprehensive income (loss) before reclassifications, net of tax		(98)	82	24
Amounts reclassified from accumulated other comprehensive (income) loss, net of tax		8	6	23
Other comprehensive income (loss), net of tax		(90)	88	47
Ending balance		(87)	8	(80)
Accumulated Other Comprehensive Loss [Member] | Accounting Standards Update 2018-02 [Member]
AOCI roll forward
Adoption of new accounting standard		(5)
Derivative Instruments [Member]
AOCI roll forward
Beginning balance	(33)	(33)	(40)	(52)
Other comprehensive income (loss) before reclassifications, net of tax				(7)
Amounts reclassified from accumulated other comprehensive (income) loss, net of tax		8	7	19
Other comprehensive income (loss), net of tax		8	7	12
Ending balance		(32)	(33)	(40)
Derivative Instruments [Member] | Foreign Currency Derivatives [Member]
AOCI roll forward
Other comprehensive income (loss) before reclassifications, net of tax				7
Outstanding derivatives					$ 0
Derivative Instruments [Member] | Accounting Standards Update 2018-02 [Member]
AOCI roll forward
Adoption of new accounting standard		(7)
Available for sale Securities [Member]
AOCI roll forward
Beginning balance	15	15	13	8
Other comprehensive income (loss) before reclassifications, net of tax		5	3	5
Amounts reclassified from accumulated other comprehensive (income) loss, net of tax			(1)
Other comprehensive income (loss), net of tax		5	2	5
Ending balance		23	15	13
Available for sale Securities [Member] | Accounting Standards Update 2018-02 [Member]
AOCI roll forward
Adoption of new accounting standard		3
Foreign Currency Translation Adjustments [Member]
AOCI roll forward
Beginning balance	29	29	(47)	(75)
Other comprehensive income (loss) before reclassifications, net of tax		(105)	76	26
Amounts reclassified from accumulated other comprehensive (income) loss, net of tax				2
Other comprehensive income (loss), net of tax		(105)	76	28
Ending balance		(76)	29	(47)
Post - Retirement Benefit Obligation [Member]
AOCI roll forward
Beginning balance	$ (3)	(3)	(6)	(8)
Other comprehensive income (loss) before reclassifications, net of tax		2	3
Amounts reclassified from accumulated other comprehensive (income) loss, net of tax				2
Other comprehensive income (loss), net of tax		2	3	2
Ending balance		(2)	$ (3)	$ (6)
Post - Retirement Benefit Obligation [Member] | Accounting Standards Update 2018-02 [Member]
AOCI roll forward
Adoption of new accounting standard		$ (1)

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Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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Amount of increase (decrease) in accumulated other comprehensive income (AOCI) for reclassification to retained earnings of tax effect from remeasurement of deferred tax pursuant to Tax Cuts and Jobs Act of 2017.

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