Restructuring Charges (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 29, 2018	Sep. 30, 2017
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	$ 1,301	$ 0
Provision	3,949	12,324
Payments and other	(4,128)	(11,023)
Restructuring reserve, ending balance	1,122	1,301
Industrial Lasers & Systems
Restructuring Reserve [Roll Forward]
Restructuring, incurred cost	2,800	11,400
OEM Laser Sources
Restructuring Reserve [Roll Forward]
Restructuring, incurred cost	1,100	900
Severance Related
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	1,301	0
Provision	1,795	5,143
Payments and other	(2,260)	(3,842)
Restructuring reserve, ending balance	836	1,301
Severance Related \| Other current liabilities
Restructuring Reserve [Roll Forward]
Restructuring reserve, ending balance	800
Asset Write-Offs
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	0	0
Provision	1,287	6,439
Payments and other	(1,287)	(6,439)
Restructuring reserve, ending balance	0	0
Other
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	0	0
Provision	867	742
Payments and other	(581)	(742)
Restructuring reserve, ending balance	$ 286	$ 0

Restructuring related payment and other during the period

No definition available.

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- Definition

Discloses the amount charged against the accrued restructuring reserves, or earnings if not previously accrued, during the period for the specified type of restructuring cost.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4(b))
-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

+ Details

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- Definition

Carrying amount as of the balance sheet date of known and estimated obligations associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid in the next twelve months or in the normal operating cycle if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4(b)(2))
-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

+ Details

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- Definition

Amount of increase (decrease) in the accrual for restructuring costs.

+ References

+ Details

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Details

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- Details

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