LONG-TERM DEBT - SCHEDULE OF LONG-TERM DEBT (DETAILS) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Dec. 31, 2011
Debt Instrument [Line Items]
Long-term Debt	$ 1,247.0	$ 1,306.9
Less current portion	210.1	207.9
Long-term debt, net of current portion	1,036.9	1,099.0
Weighted-average variable-interest rate	5.90%	5.80%
Weighted-average variable-interest rate	2.00%	1.90%
Debt Instrument, Periodic Payment	37.0
Prepayments of Long Term Debt	22.1
Long-term Debt, by Maturity [Abstract]
Remainder of 2012	168.9
2013	163.8
2014	120.1
2015	116.6
2016	113.9
Thereafter	563.7
Long-term Debt	1,247.0	1,306.9
Fixed-rate notes payable due through 2024 [Member]
Debt Instrument [Line Items]
Long-term Debt	971.0	1,002.5
Long-term Debt, by Maturity [Abstract]
Long-term Debt	971.0	1,002.5
Variable-rate notes payable due through 2024 [Member]
Debt Instrument [Line Items]
Long-term Debt	276.0	304.4
Long-term Debt, by Maturity [Abstract]
Long-term Debt	$ 276.0	$ 304.4

Prepaid long term debt

No definition available.

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Amount of the required periodic payments including both interest and principal payments.

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-SubTopic 10

-Section S99

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- Definition

Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date. May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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Total of the portions of the carrying amounts as of the balance sheet date of long-term debt, which may include notes payable, bonds payable, debentures, mortgage loans, and commercial paper, which are scheduled to be repaid within one year or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

+ References

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- Definition

Amount of long-term debt maturities after year five following the date of the latest balance sheet presented in the financial statements, which may include maturities of long-term debt, sinking fund requirements, and other securities redeemable at fixed of determinable prices and dates.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 47

-Paragraph 10

-Subparagraph b

-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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Amount of long-term debt maturing within the next twelve months following the date of the latest balance sheet presented in the financial statements, which may include maturities of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates.

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Amount of long-term debt maturing in year five following the date of the latest balance sheet presented in the financial statements, which may include maturities of long-term debt, sinking fund requirements, and other securities redeemable at fixed of determinable prices and dates.

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Amount of long-term debt maturing in year four following the date of the latest balance sheet presented in the financial statements, which may include maturities of long-term debt, sinking fund requirements, and other securities redeemable at fixed of determinable prices and dates.

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Amount of long-term debt maturing in year three following the date of the latest balance sheet presented in the financial statements, which may include maturities of long-term debt, sinking fund requirements, and other securities redeemable at fixed of determinable prices and dates.

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Amount of long-term debt maturing in year two following the date of the latest balance sheet presented in the financial statements, which may include maturities of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates.

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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.

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The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

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