FAIR VALUE MEASUREMENTS (Details) (USD $) In Millions	Jun. 30, 2011	Dec. 31, 2010
Fair Value, Liabilities Measured on Recurring Basis, Financial Statement Captions [Line Items]
Noncontrolling interest puts	$ 174.8	$ 168.7
Derivatives
Embedded derivatives related to the zero -coupon subordinated notes	0	0
Interest rate swap liability	0	2.4
Total fair value of derivatives	0	2.4
Fair market value of zero-coupon subordinated notes	222.6	419.5
Fair market value of senior notes	1,594.8	1,549.8
Fair market value of variable rate debt	336.1	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	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	174.8	168.7
Derivatives
Embedded derivatives related to the zero -coupon subordinated notes	0	0
Interest rate swap liability	0	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	0
Total fair value of derivatives	$ 0	$ 0

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This element represents a certain statement of financial position liability caption which represents a class of liabilities, or which may include an individual liability, measured at fair value on a recurring basis.

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Estimated fair value of the debt instrument (senior notes) at the balance-sheet date

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- Definition

Estimated fair value of the debt instrument (variable rate debt) at the balance-sheet date

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- Definition

Estimated fair value of the debt instrument (zero-coupon subordinated notes) at the balance-sheet date

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- Definition

Fair value of derivative liability, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 205G

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 44C
-Subparagraph a
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Fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives classified as a liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 44A, 44B

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 10

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