FAIR VALUE MEASUREMENTS (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Fair Value, Liabilities Measured on Recurring Basis, Financial Statement Captions [Line Items]
Noncontrolling interest puts	$ 20.2	$ 168.7
Derivatives
Embedded derivatives related to the zero-coupon subordinated notes	0	0
Interest rate swap liability		2.4
Total fair value of derivatives	0	2.4
Fair market value of zero-coupon subordinated notes	190.2	419.5
Fair market value of senior notes	1,624.4	1,549.8
Fair market value of variable rate debt	0	370.1
Level 1 [Member]
Fair Value, Liabilities Measured on Recurring Basis, Financial Statement Captions [Line Items]
Noncontrolling interest puts	0	0
Derivatives
Embedded derivatives related to the zero-coupon subordinated notes	0	0
Interest rate swap liability		0
Total fair value of derivatives	0	0
Level 2 [Member]
Fair Value, Liabilities Measured on Recurring Basis, Financial Statement Captions [Line Items]
Noncontrolling interest puts	20.2	168.7
Derivatives
Embedded derivatives related to the zero-coupon subordinated notes	0	0
Interest rate swap liability		2.4
Total fair value of derivatives	0	2.4
Level 3 [Member]
Fair Value, Liabilities Measured on Recurring Basis, Financial Statement Captions [Line Items]
Noncontrolling interest puts	0	0
Derivatives
Embedded derivatives related to the zero-coupon subordinated notes	0	0
Interest rate swap liability		0
Total fair value of derivatives	$ 0	$ 0