Segment Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Mar. 31, 2012	Apr. 02, 2011	Mar. 31, 2012 segments	Apr. 02, 2011
Segment Reporting Information [Line Items]
Number of reportable operating segments			2
Net sales	$ 193,284	$ 200,880	$ 384,051	$ 383,991
Income (loss) from continuing operations	20,337	26,287	45,650	51,978
Commercial Lasers and Components
Segment Reporting Information [Line Items]
Net sales	54,969	72,236	110,120	133,594
Income (loss) from continuing operations	1,150	8,993	5,170	17,318
Specialty Laser Systems
Segment Reporting Information [Line Items]
Net sales	138,315	128,644	273,931	250,397
Income (loss) from continuing operations	30,069	29,397	61,099	58,258
Corporate and other
Segment Reporting Information [Line Items]
Income (loss) from continuing operations	$ (10,882)	$ (12,103)	$ (20,619)	$ (23,598)