Discontinued Operations (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Mar. 31, 2012	Mar. 31, 2012 Y
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total minimum consideration from sale		$ 450
Initial cash payment, transactions closes	175	175
Maturity period of promissory notes		2
Total prepayment value of promissory notes	215	215
Contingent payment, percentage of quarterly cash payments of adjusted EBITDA	50.00%	50.00%
Contingent payment, based on future performance of the acquired business	11.5	11.5
Proceeds from sale of excess inventory		50
Promissory note interest rate		10.00%
Promissory note fair value	273	273
GAM Promissory Notes and Inventory Note, final maturity date		2014-03
Promissory note included in prepaid and other current assets	11	11
Promissory note included in other asset section	263	263
Discount on amortization from sale of business	1	1
After-tax gain on the sale of discontinued operations	186	186
Promissary Note [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
After-tax gain on the sale of discontinued operations	$ 186	$ 186

Amortization discount on notes receivable.

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Represents the minimum future cash payments parent company will receive for the sale of its Supermetal business under the sale agreement.

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No definition available.

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Contingent payment, percentage of quarterly cash payments of adjusted EBITDA.

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Represents the initial cash payment to Parent company upon closure of the transaction.

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Maturity period of promissory notes

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Proceeds from sale of excess inventory.

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Promissory note interest rate

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Promissory notes and inventory note, maturity date

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Total prepayment value of promissory notes.

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- Definition

Gain (loss) after tax expense or benefit, not previously recognized and resulting from the sale of a business component, which is recognized at the date of sale. A gain (loss) reflects the amount by which the consideration received exceeds (is exceeded by) the net carrying amount (reflecting previous provisions for loss on disposal, if any) of the disposal group.

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An amount representing an agreement for an unconditional promise by the maker to pay the Company (holder) a definite sum of money within one year from the balance sheet date (or the normal operating cycle, whichever is longer), net of any write-downs taken for collection uncertainty on the part of the holder. Such amount may include accrued interest receivable in accordance with the terms of the debt. The debt also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. This amount does not include amounts related to receivables held-for-sale.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. An amount representing an agreement for an unconditional promise by the maker to pay the Company (holder) a definite sum of money at a future date(s).

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- Definition

Aggregate cash proceeds received from a combination of transactions in which noncurrent assets are sold, which may include the sale of a business, an investment in an affiliate (including an equity method investee), property, plant and equipment and intangible assets. Excludes sales of trading, available-for-sale, and held-to-maturity securities.

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