Accumulated Other Comprehensive Income (Loss) - Changes (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
AOCI roll forward
Beginning balance	$ 7,126	$ 7,454
Other comprehensive income (loss), net of tax	(2)	9
Ending balance	7,146	7,429
Accumulated Other Comprehensive Income (Loss) [Member]
AOCI roll forward
Beginning balance	17	39
Other comprehensive income (loss) before reclassifications, net of tax (expense) benefit	(3)
Amounts reclassified from accumulated other comprehensive (income) loss, net of tax (expense) benefit	1
Other comprehensive income (loss), net of tax	(2)	9
Ending balance	15	$ 48
Derivative Instruments [Member]
AOCI roll forward
Amounts reclassified from accumulated other comprehensive (income) loss, net of tax (expense) benefit	1
Other comprehensive income (loss), net of tax	1
Ending balance	1
Available-for-Sale Debt Securities [Member]
AOCI roll forward
Beginning balance	43
Other comprehensive income (loss) before reclassifications, net of tax (expense) benefit	(13)
Other comprehensive income (loss), net of tax	(13)
Ending balance	30
Foreign Currency Translation Adjustments [Member]
AOCI roll forward
Beginning balance	(29)
Other comprehensive income (loss) before reclassifications, net of tax (expense) benefit	10
Other comprehensive income (loss), net of tax	10
Ending balance	(19)
Post - Retirement Benefit Obligation [Member]
AOCI roll forward
Beginning balance	3
Ending balance	$ 3