Business Segments (Schedule of Information on Company's Business Segments) (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Segment Reporting Information [Line Items]
Net sales	$ 502,572	$ 502,198
Operating income	102,557	101,757
Interest expense	10,489	10,597
Other (income) expense - net	(744)	(1,723)
Income before income taxes	92,812	92,883
Total assets	3,142,298		$ 2,805,443
Intersegment elimination
Segment Reporting Information [Line Items]
Net sales	(232)	(1,792)
Corporate office and other
Segment Reporting Information [Line Items]
Operating income	(14,947)	(18,760)
Total assets	136,120		123,008
Fluid & Metering Technologies
Segment Reporting Information [Line Items]
Segment sales	211,843	218,248
Operating income	51,401	55,898
Fluid & Metering Technologies \| External customers
Segment Reporting Information [Line Items]
Segment sales	211,709	217,932
Total assets	1,139,577		1,125,266
Fluid & Metering Technologies \| Intersegment elimination
Segment Reporting Information [Line Items]
Segment sales	134	316
Health & Science Technologies
Segment Reporting Information [Line Items]
Segment sales	186,343	179,120
Operating income	40,699	37,457
Health & Science Technologies \| External customers
Segment Reporting Information [Line Items]
Segment sales	186,251	177,750
Total assets	1,123,683		1,108,302
Health & Science Technologies \| Intersegment elimination
Segment Reporting Information [Line Items]
Segment sales	92	1,370
Fire & Safety/Diversified Products
Segment Reporting Information [Line Items]
Segment sales	104,618	106,622
Operating income	25,404	27,162
Fire & Safety/Diversified Products \| External customers
Segment Reporting Information [Line Items]
Segment sales	104,612	106,516
Total assets	742,918		$ 448,867
Fire & Safety/Diversified Products \| Intersegment elimination
Segment Reporting Information [Line Items]
Segment sales	$ 6	$ 106

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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