Debt (Schedule of Debt Repayments and Redemptions) (Details) - USD ($) $ in Millions	9 Months Ended
Dec. 31, 2016	Mar. 31, 2016
Debt Instrument, Redemption [Line Items]
Previously incurred unamortized net discount/premium and unamortized debt issuance costs of redeemed debt	$ 1	$ 0
Senior Secured Second-Priority Notes
Debt Instrument, Redemption [Line Items]
Total debt issuance and redemption costs	128
Senior Secured Second-Priority Notes \| Term Loan Due 2022 & 5.25% Senior Notes
Debt Instrument, Redemption [Line Items]
Early redemption/ call premium on redeemed debt and other fees paid to creditors	23
Previously incurred unamortized net discount/premium and unamortized debt issuance costs of redeemed debt	13
Total costs associated with redeemed debt	36
New costs incurred to issue the 5.875% Senior Notes, Term Loan A and Term Loan B	92
Revolving Credit Facility
Debt Instrument, Redemption [Line Items]
Previously incurred unamortized net discount/premium and unamortized debt issuance costs of redeemed debt	3
New costs incurred to issue the new revolving credit facility	20
Total debt issuance and redemption costs	23
Debt Issuance Costs Call Premium and Unamortized Discount \| Senior Secured Second-Priority Notes
Debt Instrument, Redemption [Line Items]
Total debt issuance and redemption costs	104
Debt Issuance Costs Call Premium and Unamortized Discount \| Senior Secured Second-Priority Notes \| Term Loan Due 2022 & 5.25% Senior Notes
Debt Instrument, Redemption [Line Items]
Early redemption/ call premium on redeemed debt and other fees paid to creditors	11
Previously incurred unamortized net discount/premium and unamortized debt issuance costs of redeemed debt	9
Total costs associated with redeemed debt	20
New costs incurred to issue the 5.875% Senior Notes, Term Loan A and Term Loan B	84
Debt Issuance Costs Call Premium and Unamortized Discount \| Revolving Credit Facility
Debt Instrument, Redemption [Line Items]
Previously incurred unamortized net discount/premium and unamortized debt issuance costs of redeemed debt	2
New costs incurred to issue the new revolving credit facility	20
Total debt issuance and redemption costs	22
Loss on Extinguishment of Debt \| Senior Secured Second-Priority Notes
Debt Instrument, Redemption [Line Items]
Total debt issuance and redemption costs	24
Loss on Extinguishment of Debt \| Senior Secured Second-Priority Notes \| Term Loan Due 2022 & 5.25% Senior Notes
Debt Instrument, Redemption [Line Items]
Early redemption/ call premium on redeemed debt and other fees paid to creditors	12
Previously incurred unamortized net discount/premium and unamortized debt issuance costs of redeemed debt	4
Total costs associated with redeemed debt	16
New costs incurred to issue the 5.875% Senior Notes, Term Loan A and Term Loan B	8
Loss on Extinguishment of Debt \| Revolving Credit Facility
Debt Instrument, Redemption [Line Items]
Previously incurred unamortized net discount/premium and unamortized debt issuance costs of redeemed debt	1
New costs incurred to issue the new revolving credit facility	0
Total debt issuance and redemption costs	$ 1

Debt Instrument, Call Premium and Unamortized Deferred Financing Costs and Debt Discount

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- Definition

Debt Instrument, Debt Issuance and Redemption Costs, Total

+ References

No definition available.

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Debt Instrument, Redemption Call Premium

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Amount of unamortized debt discount (premium) and debt issuance costs.

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- Definition

Amount, before accumulated amortization, of debt issuance costs related to line of credit arrangements. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section S45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=68176171&loc=SL68176184-208336

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
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-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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