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Pension Benefits - Summary Of Pension Plan Assets Using Fair Value Hierarchy By Asset Class (Details) - USD ($) $ in Millions | Mar. 31, 2016 | Mar. 31, 2015 | Mar. 31, 2014
--- | --- | --- | ---
U.S. Plans |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | $ 262 | $ 298 | $ 300
U.S. Plans | Total |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 262 | 298 |
U.S. Plans | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 4 | 56 |
U.S. Plans | Common and preferred stock |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 16 | 18 |
U.S. Plans | Equity commingled funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 165 | 138 |
U.S. Plans | Government securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 12 | 14 |
U.S. Plans | Corporate bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 12 | 14 |
U.S. Plans | Mortgage-backed securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 14 | 14 |
U.S. Plans | Asset-backed securities and other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 22 | 26 |
U.S. Plans | Fixed income commingled funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
U.S. Plans | Real estate funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 17 | 18 |
U.S. Plans | Other commingled funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets |  | 0 |
U.S. Plans | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
U.S. Plans | Level 1 | Total |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 20 | 73 |
U.S. Plans | Level 1 | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 4 | 55 |
U.S. Plans | Level 1 | Common and preferred stock |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 16 | 18 |
U.S. Plans | Level 1 | Equity commingled funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
U.S. Plans | Level 1 | Government securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
U.S. Plans | Level 1 | Corporate bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
U.S. Plans | Level 1 | Mortgage-backed securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
U.S. Plans | Level 1 | Asset-backed securities and other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
U.S. Plans | Level 1 | Fixed income commingled funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
U.S. Plans | Level 1 | Real estate funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
U.S. Plans | Level 1 | Other commingled funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets |  | 0 |
U.S. Plans | Level 1 | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
U.S. Plans | Level 2 | Total |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 225 | 207 |
U.S. Plans | Level 2 | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 1 |
U.S. Plans | Level 2 | Common and preferred stock |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
U.S. Plans | Level 2 | Equity commingled funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 165 | 138 |
U.S. Plans | Level 2 | Government securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 12 | 14 |
U.S. Plans | Level 2 | Corporate bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 12 | 14 |
U.S. Plans | Level 2 | Mortgage-backed securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 14 | 14 |
U.S. Plans | Level 2 | Asset-backed securities and other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 22 | 26 |
U.S. Plans | Level 2 | Fixed income commingled funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
U.S. Plans | Level 2 | Real estate funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
U.S. Plans | Level 2 | Other commingled funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets |  | 0 |
U.S. Plans | Level 2 | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
U.S. Plans | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 17 | 18 | 16
U.S. Plans | Level 3 | Total |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 17 | 18 |
U.S. Plans | Level 3 | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
U.S. Plans | Level 3 | Common and preferred stock |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
U.S. Plans | Level 3 | Equity commingled funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
U.S. Plans | Level 3 | Government securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
U.S. Plans | Level 3 | Corporate bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
U.S. Plans | Level 3 | Mortgage-backed securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
U.S. Plans | Level 3 | Asset-backed securities and other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
U.S. Plans | Level 3 | Fixed income commingled funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
U.S. Plans | Level 3 | Real estate funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 17 | 18 | 16
U.S. Plans | Level 3 | Other commingled funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets |  | 0 |
U.S. Plans | Level 3 | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Non-U.S. Plans |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 607 | 612 | 590
Non-U.S. Plans | Total |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 607 | 612 |
Non-U.S. Plans | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 4 | 8 |
Non-U.S. Plans | Common and preferred stock |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Non-U.S. Plans | Equity commingled funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 156 | 156 |
Non-U.S. Plans | Government securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 91 | 79 |
Non-U.S. Plans | Corporate bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 15 | 13 |
Non-U.S. Plans | Mortgage-backed securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Non-U.S. Plans | Asset-backed securities and other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Non-U.S. Plans | Fixed income commingled funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 186 | 191 |
Non-U.S. Plans | Real estate funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 24 | 26 |
Non-U.S. Plans | Other commingled funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets |  | 13 |
Non-U.S. Plans | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 131 | 126 |
Non-U.S. Plans | Level 1 | Total |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 121 | 112 |
Non-U.S. Plans | Level 1 | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 4 | 8 |
Non-U.S. Plans | Level 1 | Common and preferred stock |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Non-U.S. Plans | Level 1 | Equity commingled funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 6 | 7 |
Non-U.S. Plans | Level 1 | Government securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 23 | 26 |
Non-U.S. Plans | Level 1 | Corporate bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 1 | 0 |
Non-U.S. Plans | Level 1 | Mortgage-backed securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Non-U.S. Plans | Level 1 | Asset-backed securities and other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Non-U.S. Plans | Level 1 | Fixed income commingled funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 66 | 64 |
Non-U.S. Plans | Level 1 | Real estate funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Non-U.S. Plans | Level 1 | Other commingled funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets |  | 0 |
Non-U.S. Plans | Level 1 | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 21 | 7 |
Non-U.S. Plans | Level 2 | Total |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 459 | 470 |
Non-U.S. Plans | Level 2 | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Non-U.S. Plans | Level 2 | Common and preferred stock |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Non-U.S. Plans | Level 2 | Equity commingled funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 150 | 149 |
Non-U.S. Plans | Level 2 | Government securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 68 | 53 |
Non-U.S. Plans | Level 2 | Corporate bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 14 | 13 |
Non-U.S. Plans | Level 2 | Mortgage-backed securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Non-U.S. Plans | Level 2 | Asset-backed securities and other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Non-U.S. Plans | Level 2 | Fixed income commingled funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 120 | 127 |
Non-U.S. Plans | Level 2 | Real estate funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Non-U.S. Plans | Level 2 | Other commingled funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets |  | 13 |
Non-U.S. Plans | Level 2 | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 107 | 115 |
Non-U.S. Plans | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 27 | 30 | 12
Non-U.S. Plans | Level 3 | Total |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 27 | 30 |
Non-U.S. Plans | Level 3 | Cash and cash equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Non-U.S. Plans | Level 3 | Common and preferred stock |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Non-U.S. Plans | Level 3 | Equity commingled funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Non-U.S. Plans | Level 3 | Government securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Non-U.S. Plans | Level 3 | Corporate bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Non-U.S. Plans | Level 3 | Mortgage-backed securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Non-U.S. Plans | Level 3 | Asset-backed securities and other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Non-U.S. Plans | Level 3 | Fixed income commingled funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Non-U.S. Plans | Level 3 | Real estate funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 24 | 26 | $ 7
Non-U.S. Plans | Level 3 | Other commingled funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets |  | 0 |
Non-U.S. Plans | Level 3 | Other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | $ 3 | $ 4 |

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- Definition Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Section 35 -Paragraph 50 -URI http://asc.fasb.org/extlink&oid=49178875&loc=d3e12355-114930 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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