Financial Information By Reportable Segment (Detail) (USD $) In Thousands	3 Months Ended	6 Months Ended
Jul. 02, 2011	Jul. 03, 2010	Jul. 02, 2011	Jul. 03, 2010
Segment Reporting Information [Line Items]
Net sales to external customers	$ 910,175	$ 796,167	$ 1,700,448	$ 1,503,180
Operating income (loss)	109,422	100,126	195,599	163,727
Water Group
Segment Reporting Information [Line Items]
Net sales to external customers	631,994	549,318	1,147,362	1,027,356
Intersegment sales	316	427	771	944
Operating income (loss)	84,521	75,954	141,049	118,092
Technical Product Group
Segment Reporting Information [Line Items]
Net sales to external customers	278,181	246,849	553,086	475,824
Intersegment sales	1,559	1,047	2,558	1,750
Operating income (loss)	48,261	37,990	96,348	71,088
Intercompany sales eliminations
Segment Reporting Information [Line Items]
Intersegment sales	(1,875)	(1,474)	(3,329)	(2,694)
Significant Reconciling Items
Segment Reporting Information [Line Items]
Operating income (loss)	$ (23,360)	$ (13,818)	$ (41,798)	$ (25,453)

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

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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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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