Accumulated Other Comprehensive Income (Loss) Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended						9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020
AOCI Attributable to Parent, Net of Tax [Roll Forward]
AOCI, beginning balance	$ 11,205	$ 11,037	$ 10,836	$ 10,972	$ 10,613	$ 11,022	$ 10,836	$ 11,022
Other Comprehensive Income (Loss), before Tax [Abstract]
Net change, Net of Tax Amount	(63)			90			(74)	(7)
Other comprehensive income (loss)	(49)			148			(77)	(2)
Other Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Total stockholders’ equity	11,546	11,205	11,037	11,140	10,972	10,613	11,546	11,140
Foreign currency translation adjustments: [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
AOCI before tax, beginning balance	44		56	(165)		(63)	56	(63)
AOCI tax, beginning balance	0		(1)	4		(1)	(1)	(1)
AOCI, beginning balance	44		55	(161)		(64)	55	(64)
Other Comprehensive Income (Loss), before Tax [Abstract]
Net change, Before Tax Amount	(65)			93			(77)	(9)
Net change, Tax Effect	2			(3)			3	2
Other comprehensive income (loss)	(63)			90				(7)
Other Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
AOCI before tax, ending balance	(21)	44		(72)	(165)		(21)	(72)
AOCI tax, ending balance	2	0		1	4		2	1
Total stockholders’ equity	(19)	44		(71)	(161)		(19)	(71)
Unrealized gains on cash flow hedges: [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
AOCI before tax, beginning balance	46		67	(33)		31	67	31
AOCI tax, beginning balance	(8)		(12)	6		(5)	(12)	(5)
AOCI, beginning balance	38		55	(27)		26	55	26
Other Comprehensive Income (Loss), before Tax [Abstract]
Net change, Before Tax Amount	18			71			(3)	7
Net change, Tax Effect	(4)			(13)			0	(2)
Other comprehensive income (loss)	14			58			(3)	5
Other Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
OCI, before reclassifications, before tax	33			77			47	(1)
Other comprehensive income (loss) before reclassifications, tax	(6)			(14)			(9)	(1)
OCI, before reclassifications, net of tax	27			63			38	(2)
AOCI before tax, ending balance	64	46		38	(33)		64	38
AOCI tax, ending balance	(12)	(8)		(7)	6		(12)	(7)
Total stockholders’ equity	52	38		31	(27)		52	31
Unrealized gains on cash flow hedges: [Member] | Cost of revenues [Member]
Other Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Reclassification from AOCI, current period, before tax	(13)			(5)			(43)	7
Reclassification from AOCI, current period, tax	2			1			8	(1)
Reclassification from AOCI, current period, net of tax	(11)			(4)			(35)	6
Unrealized gains on cash flow hedges: [Member] | Selling, general and administrative expenses [Member]
Other Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Reclassification from AOCI, current period, before tax	(2)			(1)			(7)	1
Reclassification from AOCI, current period, tax	0			0			1	0
Reclassification from AOCI, current period, net of tax	(2)			(1)			(6)	1
Accumulated other comprehensive income (loss):
AOCI Attributable to Parent, Net of Tax [Roll Forward]
AOCI before tax, beginning balance	90		123	(198)		(32)	123	(32)
AOCI tax, beginning balance	(8)		(13)	10		(6)	(13)	(6)
AOCI, beginning balance	82	81	110	(188)	(264)	(38)	110	(38)
Other Comprehensive Income (Loss), before Tax [Abstract]
Net change, Before Tax Amount	(47)			164			(80)	(2)
Net change, Tax Effect	(2)			(16)			3	0
Other comprehensive income (loss)	(49)	1	(29)	148	76	(226)	(77)	(2)
Other Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
AOCI before tax, ending balance	43	90		(34)	(198)		43	(34)
AOCI tax, ending balance	(10)	(8)		(6)	10		(10)	(6)
Total stockholders’ equity	$ 33	$ 82	$ 81	$ (40)	$ (188)	$ (264)	$ 33	$ (40)