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Percentage of principal at which debt was extinguished.

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No definition available.

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- Definition

Tax exempt Industrial Development Revenue Bonds.

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No definition available.

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 32

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Name Accounting Standards Codification

-Topic 230

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-Section 50

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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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-Section 02

-Paragraph 22

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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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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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Equity and Financing Arrangements (Details) (USD $) In Millions, except Share data, unless otherwise specified	6 Months Ended			3 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012 Issuance of Debt [Member]	Jun. 30, 2012 Repayment of Debt [Member]	Jun. 30, 2012 Debt Conversion [Member]
Common Stock Disclosures [Abstract]
Common stock issued during period	0	0
Dilutive Securities [Abstract]
Dilutive Securities	$ 0
Debt Instruments [Line Items]
Unsecured debt			28.0
Interest rate			4.38%	5.875%
Redeemed and retired debt				28.0
Extinguishment of debt at principal percent				100.00%	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%	100.00%