Redeemable Noncontrolling Interests and Noncontrolling Interests - Schedule of Changes in Redeemable Noncontrolling Interests and Noncontrolling Interests (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Noncontrolling Interests
Beginning balance			$ 193
Net income attributable to noncontrolling interests	$ 53	$ 54	107	$ 112
Other comprehensive loss	(18)	(7)	(12)	(44)
Payments to noncontrolling interests	(37)	(42)	(76)	(106)
Ending balance	210		210
Redeemable Noncontrolling Interests
Beginning balance			1,393
Other comprehensive loss	(18)	(7)	(12)	(44)
Payments to noncontrolling interests	(37)	(42)	(76)	(106)
Ending balance	1,384		1,384
Noncontrolling Interests
Noncontrolling Interests
Beginning balance	194	240	193	253
Net income attributable to noncontrolling interests	42	43	85	89
Other comprehensive loss	0	0	0	0
Payments to noncontrolling interests	(37)	(42)	(76)	(106)
Other	11	(33)	8	(28)
Ending balance	210	208	210	208
Redeemable Noncontrolling Interests
Other comprehensive loss	0	0	0	0
Payments to noncontrolling interests	(37)	(42)	(76)	(106)
Other	11	(33)	8	(28)
Redeemable Noncontrolling Interest
Noncontrolling Interests
Other comprehensive loss	(18)	(7)	(12)	(44)
Payments to noncontrolling interests	0	0	0	0
Other	3	0	3	0
Redeemable Noncontrolling Interests
Beginning balance	1,399	1,422	1,393	1,459
Net income attributable to noncontrolling interests	11	11	22	23
Other comprehensive loss	(18)	(7)	(12)	(44)
Reclassification of recurring compensation to other accrued liabilities	(11)	(11)	(22)	(23)
Payments to noncontrolling interests	0	0	0	0
Other	3	0	3	0
Ending balance	$ 1,384	$ 1,415	$ 1,384	$ 1,415

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Reclassification of Temporary Equity to Liability

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which is directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent (that is, noncontrolling interest, previously referred to as minority interest).

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Amount of Net Income (Loss) attributable to noncontrolling interest.

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