Number of Customers, Minimum Ten Percent of Net Sales

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13537-108611

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- Definition

Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(1)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

The net result for the period of deducting operating expenses from operating revenues.

+ References

No definition available.

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The net amount of other operating income and expenses, the components of which are not separately disclosed on the income statement, from items that are associated with the entity's normal revenue producing operations.

+ References

No definition available.

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- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Segment and Geographic Information (Details) $ in Thousands	3 Months Ended								12 Months Ended
Segment and Geographic Information (Details) $ in Thousands	Sep. 29, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 30, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jul. 01, 2017 USD ($)	Apr. 01, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 29, 2018 USD ($) customers	Sep. 30, 2017 USD ($)	Oct. 01, 2016 USD ($)
Segment Reporting Information [Line Items]
Net sales	$ 461,548	$ 482,342	$ 481,118	$ 477,565	$ 490,298	$ 464,107	$ 422,833	$ 346,073	$ 1,902,573	$ 1,723,311	$ 857,385
Income (loss) from continuing operations:									393,017	325,495	127,614
Total other expense, net									(31,462)	(23,440)	(4,718)
Income from continuing operations before income taxes									$ 361,555	$ 302,055	$ 122,896
Number of customers, minimum ten percent of net sales \| customers									1
Customer one
Segment Reporting Information [Line Items]
Number of customers, minimum ten percent of net sales \| customers									1
Customer two
Segment Reporting Information [Line Items]
Number of customers, minimum ten percent of net sales \| customers									2
Sales \| Customer concentration risk \| Customer one
Segment Reporting Information [Line Items]
Concentration Risk, Percentage									25.80%	22.90%	13.10%
Sales \| Customer concentration risk \| Customer two
Segment Reporting Information [Line Items]
Concentration Risk, Percentage											16.40%
Operating Segments \| OEM Laser Sources
Segment Reporting Information [Line Items]
Net sales									$ 1,259,477	$ 1,143,620	$ 722,517
Income (loss) from continuing operations:									469,835	432,839	197,923
Operating Segments \| Industrial Lasers & Systems
Segment Reporting Information [Line Items]
Net sales									643,096	579,691	134,868
Income (loss) from continuing operations:									(3,687)	(26,447)	(13,869)
Corporate
Segment Reporting Information [Line Items]
Income (loss) from continuing operations:									$ (73,131)	$ (80,897)	$ (56,440)