Schedule of Information on Company's Business Segments (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended			9 Months Ended
	Sep. 30, 2013		Sep. 30, 2012	Sep. 30, 2013		Sep. 30, 2012	Dec. 31, 2012
Segment Reporting Information [Line Items]
Total group sales	$ 490,617		$ 479,859	$ 1,503,510		$ 1,463,420
Total operating income	97,369		80,588	291,640		253,807
Interest expense	10,570		10,536	31,724		31,734
Other income-net	(188)		132	518		19
Income before income taxes	86,611		70,184	260,434		222,092
Total assets	2,849,381			2,849,381			2,785,390
Fluid & Metering Technologies:
Segment Reporting Information [Line Items]
Total assets	1,053,338			1,053,338			1,023,143
Health & Science Technologies:
Segment Reporting Information [Line Items]
Total assets	1,133,401			1,133,401			1,102,868
Fire & Safety/Diversified Products:
Segment Reporting Information [Line Items]
Total assets	495,163			495,163			488,886
Corporate office and other
Segment Reporting Information [Line Items]
Total assets	167,479	[1]		167,479	[1]		170,493	[1]
External customers | Fluid & Metering Technologies:
Segment Reporting Information [Line Items]
Sales	212,054		197,620	648,675		620,451
External customers | Health & Science Technologies:
Segment Reporting Information [Line Items]
Sales	177,674		174,351	528,459		516,314
External customers | Fire & Safety/Diversified Products:
Segment Reporting Information [Line Items]
Sales	100,889		107,888	326,376		326,655
Intersegment sales | Fluid & Metering Technologies:
Segment Reporting Information [Line Items]
Sales	283		380	905		982
Intersegment sales | Health & Science Technologies:
Segment Reporting Information [Line Items]
Sales	954		1,874	3,904		4,260
Intersegment sales | Fire & Safety/Diversified Products:
Segment Reporting Information [Line Items]
Sales	188		311	450		1,518
Total group sales | Fluid & Metering Technologies:
Segment Reporting Information [Line Items]
Total group sales	212,337		198,000	649,580		621,433
Total operating income	51,736		41,649	155,930		132,477
Total group sales | Health & Science Technologies:
Segment Reporting Information [Line Items]
Total group sales	178,628		176,225	532,363		520,574
Total operating income	36,775		27,305	103,564		84,711
Total group sales | Fire & Safety/Diversified Products:
Segment Reporting Information [Line Items]
Total group sales	101,077		108,199	326,826		328,173
Total operating income	22,119		24,738	74,027		74,524
Total group sales | Corporate office and other
Segment Reporting Information [Line Items]
Total operating income	(13,261)		(13,104)	(41,881)		(37,905)
Intersegment elimination
Segment Reporting Information [Line Items]
Total group sales	$ (1,425)		$ (2,565)	$ (5,259)		$ (6,760)

[1] Includes intersegment eliminations.