Business Segments (Details Textual) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012 Customers	Dec. 31, 2011 Customers	Dec. 31, 2010 Customers
Segment Reporting Information [Line Items]
Investments in joint ventures	$ 13,319	$ 14,872	$ 14,160
Change in the identifiable assets of the Air and Liquid / Long-lived assets	99,715	108,419	124,089
Business Segments (Textual) [Abstract]
Estimated costs of asbestos-related litigation, net of estimated insurance recoveries	19,980
Sales to individual countries	10.00%	10.00%
CHINA [Member]
Segment Reporting Information [Line Items]
Net sales			10.00%
Forged and Cast Rolls [Member]
Segment Reporting Information [Line Items]
Investments in joint ventures	13,319	14,872	14,160
Net sales	23.00%	22.00%	12.00%
Number of customers accounted for net sales	2	2	1
Air and Liquid Processing [Member] \| U.S. [Member]
Segment Reporting Information [Line Items]
Change in the identifiable assets of the Air and Liquid / Long-lived assets	$ 118,115	$ 126,206	$ 142,089

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Entity wide revenue individual countries percentage maximum.

+ References

No definition available.

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- Definition

Entity wide revenue number of major customers.

+ References

No definition available.

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- Definition

Percentage of revenue generated from a single external customer that accounts for 10 percent or more of an entity's revenues.

+ References

No definition available.

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- Definition

Carrying amount due after one year of the balance sheet date (or one operating cycle, if longer) of amount due in settlement of a claim for reimbursement from an insurance company when the Company has suffered a loss covered under an insurance policy.

+ References

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 210.5-02.17)

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

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- Definition

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.

+ References

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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- Definition

Increase in asbestos and environmental reserve based on known and estimated costs of settling insured claims and costs incurred in the claims settlement process, net of estimated reinsurance recoveries.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 40

-Section 50

-Paragraph 3

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6482485&loc=d3e14764-158437

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-PLI

-Paragraph 132, 133, 135, 136, 137

-IssueDate 2006-09-01

-Chapter 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Statement of Position (SOP)

-Number 94-5

-Paragraph 11, 12

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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