Segment Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2012 segments	Mar. 31, 2011
Segment Reporting Information [Line Items]
Number of operating segments (in segments)	3
Summarized financial information of the reportable segments
Sales to external customers	$ 1,074,980	$ 997,207
Intersegment sales	0	0
Segment operating income	142,523	130,253
Gain from sale of manufacturing facility	10,410	493
EPD [Member]
Summarized financial information of the reportable segments
Sales to external customers	519,842	499,760
Intersegment sales	14,966	24,011
Segment operating income	92,177	91,756
Gain from sale of manufacturing facility	10,400
IPD [Member]
Summarized financial information of the reportable segments
Sales to external customers	193,382	160,912
Intersegment sales	19,804	15,413
Segment operating income	17,351	13,076
FCD [Member]
Summarized financial information of the reportable segments
Sales to external customers	361,756	336,535
Intersegment sales	2,135	1,062
Segment operating income	55,693	47,534
Reportable Segment [Member]
Summarized financial information of the reportable segments
Sales to external customers	1,074,980	997,207
Intersegment sales	36,905	40,486
Segment operating income	165,221	152,366
Eliminations and All Others [Member]
Summarized financial information of the reportable segments
Sales to external customers	0	0
Intersegment sales	(36,905)	(40,486)
Segment operating income	$ (22,698)	$ (22,113)

Number of operating segments.

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- Definition

The difference between the sale price or salvage price and the book value of a property, plant, and equipment asset that was sold or retired during the reporting period. This element refers to the gain (loss).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

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The net result for the period of deducting operating expenses from operating revenues.

+ References

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- Definition

Amount of revenue from transactions with other operating segments of the same entity.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 131

-Paragraph 27

-Subparagraph b

-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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- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 5

-Section 03

-Paragraph 1

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

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