Goodwill (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Goodwill by Segment
Goodwill	$ 240.4	$ 219.5
Additional goodwill impairment charges	0	0
Accumulated goodwill impairment losses	325.0	325.0
Rail Group
Goodwill by Segment
Goodwill	122.5	122.5
Construction Products Group
Goodwill by Segment
Goodwill	105.2	84.3
Energy Equipment Group
Goodwill by Segment
Goodwill	10.9	10.9
Railcar Leasing and Management Services Group
Goodwill by Segment
Goodwill	$ 1.8	$ 1.8

Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

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+ Details

- Definition

Loss recognized during the period that results from the write-down of goodwill after comparing the implied fair value of reporting unit goodwill with the carrying amount of that goodwill. Goodwill is assessed at least annually for impairment.

+ References

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+ Details