Share-Based Compensation - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Mar. 31, 2016	Jul. 31, 2013
Share-based Compensation [Abstract]
Non-cash credits	$ 14
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options vested and exercisable (in shares)	2,000,000
Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options vested and exercisable (in shares)	146,000
Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock award contractual term	7 years
Stock award vesting period	4 years
RSUs \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock award vesting period	3 years
RSUs \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock award vesting period	4 years
PeRSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock award vesting period	4 years
TSRUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock award vesting period	3 years
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	21,000,000
Number of shares available for grant	4,000,000
Period over which payroll is deducted to purchase shares	3 months
Percentage of market price for share purchase	85.00%
Percentage of market price deduction for share purchases	15.00%
2013 Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized		30,000,000
Number of shares available for grant	29,000,000

Employee service share based compensation period to purchase shares through payroll deductions

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- Definition

Restructuring Charge, Non-Cash Credits, Share-based Compensation

+ References

No definition available.

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- References

No definition available.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Discount rate from fair value on offering date that participants pay for shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

+ References

No definition available.

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