Stockholders' Equity - Schedule of Other Comprehensive Income (Loss), Net of Tax (Details) - USD ($)	3 Months Ended		9 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net actuarial losses attributable to redeemable noncontrolling interest	$ 0	$ 2,000,000	$ 1,000,000	$ 3,000,000
Other comprehensive income (loss) before reclassifications	(5,000,000)		573,000,000
Reclassified to income statement, net of income tax expense	1,000,000		3,000,000
Other Comprehensive Income (Loss), Net of Tax	(4,000,000)	(404,000,000)	576,000,000	(762,000,000)
Foreign currency translation adjustments arising during period, tax	0	0	0	1,000,000
Reclassified to income statement, tax	0	0	0	0
Unrealized gains on cash flow hedges arising during period, tax	2,000,000	0	2,000,000	0
Net actuarial loss and prior service cost arising during the period, tax	0	0	0	0
Amortization of actuarial loss and prior service costs, tax	0	1,000,000	0	3,000,000
Foreign currency translation adjustments and other, tax	0	0	0	0
Foreign Currency Translation Adjustments, Net of Tax
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications	30,000,000	(398,000,000)	715,000,000	(782,000,000)
Reclassified to income statement, net of income tax expense	0	0	0	20,000,000
Other Comprehensive Income (Loss), Net of Tax	30,000,000	(398,000,000)	715,000,000	(762,000,000)
Unrealized Gains (Losses) on Net Investment Hedges, Net of Tax
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications	(19,000,000)	0	(127,000,000)	0
Reclassified to income statement, net of income tax expense	0	0	0	0
Other Comprehensive Income (Loss), Net of Tax	(19,000,000)	0	(127,000,000)	0
Unrealized gains (losses) on net investment hedges arising during period, tax	9,000,000	0	78,000,000	0
Reclassified to income statement, tax	0	0	0	0
Unrealized Gains (Losses) on Cash Flow Hedges, Net of Tax
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications	(16,000,000)		(5,000,000)
Reclassified to income statement, net of income tax expense	0		0
Other Comprehensive Income (Loss), Net of Tax	(16,000,000)	(14,000,000)	(5,000,000)	(20,000,000)
Accumulated Defined Benefit Plans Adjustment, Net Prior Service and Net Gain (Loss)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications	0	0	0	0
Accumulated Defined Benefit Plans Adjustment, Amortization of Actuarial Loss and Prior Service Cost
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications	1,000,000	2,000,000	3,000,000	6,000,000
Accumulated Defined Benefit Plans, Foreign Currency Adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications	0	6,000,000	(10,000,000)	14,000,000
Accumulated Defined Benefit Plans Adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), Net of Tax	$ 1,000,000	$ 8,000,000	$ (7,000,000)	$ 20,000,000