Guarantor Financial Information (CONDENSED CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (LOSS)) (Details) - USD ($) $ in Millions	3 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Condensed Income Statements, Captions [Line Items]
Net operating revenues	$ 8,012	$ 8,027
Cost of Services (exclusive of depreciation and amortization included below)	2,099	2,393
Cost of Products (exclusive of depreciation and amortization included below)	1,419	1,365
Net operating expenses
Selling, general and administrative	1,917	2,187
Severance and exit costs	16	13
Depreciation	1,680	1,241
Amortization	287	347
Other Cost and Expense, Operating	233
Other, net	233	(20)
Total costs and expenses	7,651	7,526
Operating Income	361	501
Other (expense) income
Interest Income	10	3
Interest Expense	(615)	(542)
(Losses) earnings of Subsidiaries	0	0
Other income, net	(2)	1
Nonoperating Expense	(607)	(538)
Loss (income) before income taxes	(246)	(37)
Income tax benefit	(56)	17
Net (loss) income	(302)	(20)
Other Comprehensive Income (Loss), Net of Tax	(1)	4
Comprehensive (loss) income	(303)	(16)
Consolidation, Eliminations [Member]
Condensed Income Statements, Captions [Line Items]
Net operating revenues	0	0
Cost of Services (exclusive of depreciation and amortization included below)	0	0
Cost of Products (exclusive of depreciation and amortization included below)	0	0
Net operating expenses
Selling, general and administrative	0	0
Severance and exit costs	0	0
Depreciation	0	0
Amortization	0	0
Other Cost and Expense, Operating	0
Other, net		0
Total costs and expenses	0	0
Operating Income	0	0
Other (expense) income
Interest Income	(219)	(235)
Interest Expense	219	235
(Losses) earnings of Subsidiaries	208	(328)
Other income, net	0	0
Nonoperating Expense	208	(328)
Loss (income) before income taxes	208	(328)
Income tax benefit	0	0
Net (loss) income	208	(328)
Other Comprehensive Income (Loss), Net of Tax	0	(8)
Comprehensive (loss) income	208	(336)
Parent Company [Member]
Condensed Income Statements, Captions [Line Items]
Net operating revenues	0	0
Cost of Services (exclusive of depreciation and amortization included below)	0	0
Cost of Products (exclusive of depreciation and amortization included below)	0	0
Net operating expenses
Selling, general and administrative	0	0
Severance and exit costs	0	0
Depreciation	0	0
Amortization	0	0
Other Cost and Expense, Operating	0
Other, net		0
Total costs and expenses	0	0
Operating Income	0	0
Other (expense) income
Interest Income	198	198
Interest Expense	(198)	(198)
(Losses) earnings of Subsidiaries	(302)	(20)
Other income, net	0	0
Nonoperating Expense	(302)	(20)
Loss (income) before income taxes	(302)	(20)
Income tax benefit	0	0
Net (loss) income	(302)	(20)
Other Comprehensive Income (Loss), Net of Tax	(1)	4
Comprehensive (loss) income	(303)	(16)
Guarantor Subsidiaries [Member]
Condensed Income Statements, Captions [Line Items]
Net operating revenues	0	0
Cost of Services (exclusive of depreciation and amortization included below)	0	0
Cost of Products (exclusive of depreciation and amortization included below)	0	0
Net operating expenses
Selling, general and administrative	0	0
Severance and exit costs	0	0
Depreciation	0	0
Amortization	0	0
Other Cost and Expense, Operating	0
Other, net		0
Total costs and expenses	0	0
Operating Income	0	0
Other (expense) income
Interest Income	28	39
Interest Expense	(423)	(407)
(Losses) earnings of Subsidiaries	94	348
Other income, net	(1)	0
Nonoperating Expense	(302)	(20)
Loss (income) before income taxes	(302)	(20)
Income tax benefit	0	0
Net (loss) income	(302)	(20)
Other Comprehensive Income (Loss), Net of Tax	(1)	4
Comprehensive (loss) income	(303)	(16)
Non-Guarantor Subsidiaries [Member]
Condensed Income Statements, Captions [Line Items]
Net operating revenues	8,012	8,027
Cost of Services (exclusive of depreciation and amortization included below)	2,099	2,393
Cost of Products (exclusive of depreciation and amortization included below)	1,419	1,365
Net operating expenses
Selling, general and administrative	1,917	2,187
Severance and exit costs	16	13
Depreciation	1,680	1,241
Amortization	287	347
Other Cost and Expense, Operating	233
Other, net		(20)
Total costs and expenses	7,651	7,526
Operating Income	361	501
Other (expense) income
Interest Income	3	1
Interest Expense	(213)	(172)
(Losses) earnings of Subsidiaries	0	0
Other income, net	(1)	1
Nonoperating Expense	(211)	(170)
Loss (income) before income taxes	150	331
Income tax benefit	(56)	17
Net (loss) income	94	348
Other Comprehensive Income (Loss), Net of Tax	1	4
Comprehensive (loss) income	$ 95	$ 352