Cleveland-Cliffs Inc. Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

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FAIR VALUE OF FINANCIAL INSTRUMENTS (Fair Value, Assets and Liabilities Measured On Recurring Basis, Unobservable Input Reconciliation) (Details)

v2.4.0.6

FAIR VALUE OF FINANCIAL INSTRUMENTS (Fair Value, Assets and Liabilities Measured On Recurring Basis, Unobservable Input Reconciliation) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Fair Value, Assets Measured On Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Beginning balance - January 1	$ 62.4	$ 157.9
Total gains
Included in earnings	28.0	43.3
Included in other comprehensive income	0	0
Settlements	(37.1)	(132.0)
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Ending balance - December 31	53.3	69.2
Total gains (losses) for the period included in earnings attributable to the change in unrealized gains (losses) on assets (liabilities) still held at the reporting date	28.0	43.3
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Beginning balance - January 1	(11.3)	(19.5)
Total gains
Included in earnings	(6.8)	(1.1)
Included in other comprehensive income	0	0
Settlements	11.3	19.5
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Ending balance - December 31	(6.8)	(1.1)
Total gains (losses) for the period included in earnings attributable to the change in unrealized gains (losses) on assets (liabilities) still held at the reporting date	$ (6.8)	$ (1.1)

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