Accumulated Other Comprehensive Income (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Accumulated other comprehensive income [Roll Forward]
Accumulated other comprehensive income (loss)	$ (575)	$ (189)	$ (731)
Foreign currency translation
Accumulated other comprehensive income [Roll Forward]
Foreign currency translation, beginning	504	466	671
Purchase of noncontrolling interests	8	0	0
Other comprehensive income (loss)	(341)	38	(205)
Foreign currency translation, ending	171	504	466
Pension and postretirement
Accumulated other comprehensive income [Roll Forward]
Pension and post retirement, beginning	(692)	(1,213)	(1,164)
Actuarial gains (losses) deferred during the period, net of taxes of: 2014, $87; 2013, $(233); 2012, $81	(152)	375	(160)
Amortization of deferred losses into earnings, net of taxes of: 2014, $(52); 2013 $(85); 2012, $(62)	98	146	111
Pension and post retirement, ending	(746)	(692)	(1,213)
Cash flow hedges
Accumulated other comprehensive income [Roll Forward]
Cash flow hedges, beginning	(1)	16	(69)
Gains (losses) deferred during the period, net of taxes of: 2014, $0; 2013, $7; 2012, $(37)	(1)	(11)	64
Reclassification of (gains) losses to sales and cost of sales, net of taxes of: 2014, $0; 2013, $3; 2012, $(13)	2	(6)	21
Cash flow hedges, ending	$ 0	$ (1)	$ 16

Foreign currency translation on purchase of noncontrolling interest.

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Accumulated change, net of tax, in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

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The total of net gain (loss), prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost.

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Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses.

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Amount after tax of (increase) decrease in the value of the projected benefit obligation related to a change in an actuarial assumption and increase (decrease) in the value of the plan assets resulting from experience different from that assumed, that has not been recognized in net periodic benefit (cost) credit.

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Amount after tax and 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, attributable to parent entity.

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Amount after tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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Amount after tax of reclassification adjustment from accumulated other comprehensive (income) loss related to net period benefit cost (credit) for pension and other postretirement defined benefit plans.

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Amount after tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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