Accumulated Other Comprehensive Loss - Changes (Detail) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020 USD ($) $ / $	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) $ / $	Jun. 30, 2019 USD ($)	Dec. 31, 2019 $ / $
AOCI roll forward
Beginning balance	$ 6,745	$ 6,417	$ 7,070	$ 6,276
Other comprehensive income (loss), net of tax	50	31	(33)	65
Ending balance	$ 6,893	6,467	$ 6,893	6,467
Dollar exchange rate | $ / $	0.7366		0.7366		0.7698
Accumulated Other Comprehensive Loss [Member]
AOCI roll forward
Beginning balance	$ (91)	(53)	$ (8)	(87)
Other comprehensive income (loss) before reclassifications, net of tax			(36)
Amounts reclassified from accumulated other comprehensive (income) loss, net of tax			3
Other comprehensive income (loss), net of tax	50	31	(33)	65
Ending balance	(41)	$ (22)	(41)	$ (22)
Derivative Instruments [Member]
AOCI roll forward
Beginning balance			(24)
Other comprehensive income (loss) before reclassifications, net of tax			1
Amounts reclassified from accumulated other comprehensive (income) loss, net of tax			4
Other comprehensive income (loss), net of tax			5
Ending balance	(19)		(19)
Available for sale Securities [Member]
AOCI roll forward
Beginning balance			38
Other comprehensive income (loss) before reclassifications, net of tax			5
Other comprehensive income (loss), net of tax			5
Ending balance	43		43
Foreign Currency Translation Adjustments [Member]
AOCI roll forward
Beginning balance			(21)
Other comprehensive income (loss) before reclassifications, net of tax			(42)
Other comprehensive income (loss), net of tax			(42)
Ending balance	(63)		(63)
Post - Retirement Benefit Obligation [Member]
AOCI roll forward
Beginning balance			(1)
Amounts reclassified from accumulated other comprehensive (income) loss, net of tax			(1)
Other comprehensive income (loss), net of tax			(1)
Ending balance	$ (2)		$ (2)