Goodwill By Reportable Segment (Details) (USD $) In Thousands, unless otherwise specified	Apr. 03, 2015	Dec. 31, 2014
Goodwill [Line Items]
Goodwill	$ 249,528us-gaap_GoodwillGross	$ 241,975us-gaap_GoodwillGross
Accumulated impairment of goodwill	(151,229)	(151,229)
Total	98,299us-gaap_Goodwill	90,746us-gaap_Goodwill
Laser Products
Goodwill [Line Items]
Goodwill	132,954	132,954
Accumulated impairment of goodwill	(102,461)	(102,461)
Total	30,493	30,493
Medical Technologies
Goodwill [Line Items]
Goodwill	82,730	82,730
Accumulated impairment of goodwill	(31,722)	(31,722)
Total	51,008	51,008
Precision Motion
Goodwill [Line Items]
Goodwill	33,844	26,291
Accumulated impairment of goodwill	(17,046)	(17,046)
Total	$ 16,798	$ 9,245

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

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-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

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-Paragraph 1

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