This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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Amount before tax, after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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The cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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Equity Investments (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended			6 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013	Sep. 30, 2013
Schedule of Equity Method Investments [Line Items]
Impairment of an equity investment	$ 0	$ 0	$ 191
Distribution Solutions [Member] \| Brocacef [Member]
Schedule of Equity Method Investments [Line Items]
Equity interest in investee	45.00%
Distribution Solutions [Member] \| Nadro [Member]
Schedule of Equity Method Investments [Line Items]
Equity interest in investee		49.00%	49.00%	49.00%
Impairment of an equity investment			191
Cumulative foreign currency translation losses			69
Proceeds from sale of equity investments				$ 41