Investments in and Loans to Joint Ventures (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Carrying amount of investments in and loans to joint ventures
Total investments in and loans to joint ventures	$ 41,534	$ 44,536
Ohio Castings [Member]
Carrying amount of investments in and loans to joint ventures
Total investments in and loans to joint ventures	6,909	7,022
Axis [Member]
Carrying amount of investments in and loans to joint ventures
Total investments in and loans to joint ventures	25,146	27,181
Amtek Railcar [Member]
Carrying amount of investments in and loans to joint ventures
Total investments in and loans to joint ventures	$ 9,479	$ 10,333

Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.12)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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