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Short-Term and Long-Term Debt (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended |
--- | --- | ---
Mar. 31, 2012 | Dec. 31, 2011
Short-Term and Long-Term Debt [Abstract] |  |
Short-Term Debt Outstanding | $ 7.1 | $ 6.5
Long-Term Debt Outstanding | $ 856.5 | $ 857.9
Debt Instrument, Required Indebtedness to Total Capital Ratio | 0.65 to 1.00 |
Debt Instrument, Actual Indebtedness to Total Capital Ratio | 0.43 to 1.00 |

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- Definition Actual indebtedness to total capital ratio required to be maintained by most restrictive financial covenant. + References No definition available. + Details
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- Definition Indebtedness to total capital ratio required to be maintained by most restrictive financial covenant. + References No definition available. + Details
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- Details
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- Definition Carrying value as of the balance sheet date of the sum of short-term debt and current maturities of long-term debt and capital lease obligations, which are due within one year (or one business cycle if longer). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19,20) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Sum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year (current maturities) or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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