Contingencies (Details) (USD $) In Millions	9 Months Ended
Sep. 30, 2011
Purchase replacement coal	$ 100
Damages and interest awarded	104.1
Appeal Bond	124.9
Amount accrued	106.7
Interest recognized post-acquisition	1.8
Maximum [Member]
Aggregate amount of past and future damages	377.0
Minimum [Member]
Aggregate amount of past and future damages	$ 228.0

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

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+ Details