v2.4.0.6

Equity and Financing Arrangements (Details) (USD $) In Millions, except Share data, unless otherwise specified	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Oct. 25, 2012
Common Stock Disclosures [Abstract]
Common stock issued during period	0	0
Preferred Stock, Shares Authorized	1,175,000
Preferred Stock, Par or Stated Value Per Share	$ 25
Preferred Stock, Shares Issued			0
Preferred Stock, Shares Outstanding			0
Dilutive Securities [Abstract]
Dilutive Securities	$ 0
Issuance of Debt [Member]
Debt Instruments [Line Items]
Unsecured debt	28.0
Interest rate	4.38%
Repayment of Debt [Member]
Debt Instruments [Line Items]
Interest rate	5.875%
Redeemed and retired debt	28.0
Extinguishment of debt at principal percent	100.00%
Remarketing of debt [Abstract]
Extinguishment of debt at principal percent	100.00%
Debt Conversion [Member]
Debt Instruments [Line Items]
Extinguishment of debt at principal percent	100.00%
Remarketing of debt [Abstract]
Tax exempt debt	$ 19.3
Interest rate before remarketing	4.875%
Interest rate after remarketing	3.45%
Extinguishment of debt at principal percent	100.00%

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Percentage of principal at which debt was extinguished.

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Tax exempt Industrial Development Revenue Bonds.

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The dividend or interest rate, if any, associated with the financial instrument issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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The rate of interest that was being paid on the original debt issue that is being converted in the noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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Interest rate stated in the contractual debt agreement.

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Includes adjustments resulting from the assumption that dilutive convertible securities were converted, options or warrants were exercised, or that other shares were issued upon the satisfaction of certain conditions.

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Gross amount of debt extinguished.

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Face amount or stated value per share of nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer); generally not indicative of the fair market value per share.

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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Number of new stock issued during the period.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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