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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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LONG-TERM DEBT - SCHEDULE OF LONG-TERM DEBT (DETAILS) (USD $) In Millions, unless otherwise specified							6 Months Ended
	Jun. 30, 2012	Dec. 31, 2011	Jun. 30, 2012 Fixed-rate notes payable due through 2024 [Member]	Dec. 31, 2011 Fixed-rate notes payable due through 2024 [Member]	Jun. 30, 2012 Variable-rate notes payable due through 2023 [Member]	Dec. 31, 2011 Variable-rate notes payable due through 2023 [Member]	Jun. 30, 2012 Scheduled debt payments [Member]	Jun. 30, 2012 Debt prepayments [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 1,140.5	$ 1,306.9	$ 933.3	$ 1,002.5	$ 207.2	$ 304.4
Less current portion	183.4	207.9
Long-term debt, net of current portion	957.1	1,099.0
Weighted-average fixed-interest rate	5.90%	5.80%
Weighted-average variable-interest rate	2.00%	1.90%
Debt payments							62.9	102.5
Long-term Debt, Fiscal Year Maturity [Abstract]
Remainder of 2012	108.6
2013	160.9
2014	117.1
2015	113.4
2016	110.6
Thereafter	529.9
Long-term Debt	$ 1,140.5	$ 1,306.9	$ 933.3	$ 1,002.5	$ 207.2	$ 304.4