CASH FLOW INFORMATION (Reconciliation Of Capital Additions To Cash Paid For Capital Expenditures) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Payments To Acquire Property Plant And Equipment Net	$ 861.6	[1]	$ 1,127.5	[1]	$ 862.1	[1]
Property, Plant and Equipment, Additions	752.3	[2]	1,335.3	[2]	960.9	[2]
Non-cash accruals	(109.3)		152.5		60.1
Capital leases	0		55.3		38.7
Total	(109.3)		207.8		98.8
Pinnacle [Member]
Sale Leaseback Transaction, Net Proceeds					$ 18.6

[1] Cash paid for capital expenditures for 2011 has been shown net of cash proceeds of $18.6 million from the Pinnacle longwall sale-leaseback that was completed in October 2011. The adjustment was necessary in 2011 due to the timing of the cash payments related to the longwall.

[2] Includes capital lease additions and non-cash accruals. Refer to NOTE 21 - CASH FLOW INFORMATION.