Significant Accounting Policies - Asset Retirement Obligations (Details) - USD ($) $ in Thousands	12 Months Ended
Oct. 03, 2020	Sep. 28, 2019
Property, Plant and Equipment [Line Items]
Asset retirement obligation gross expected future cash flows	$ 6,800
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Asset retirement liability, beginning of period	5,074	$ 5,802
Adjustments and additions to asset retirement obligations recognized		390
Asset retirement obligation, liabilities settled	(32)	(1,155)
Adjustments and additions to asset retirement obligations recognized	813
Accretion recognized	161	127
Changes due to foreign currency exchange	163	(90)
Asset retirement liability, end of period	6,179	5,074
Other current liabilities
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Asset retirement liability, beginning of period	100
Asset retirement liability, end of period	300	100
Other long-term liabilities
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Asset retirement liability, beginning of period	4,900
Asset retirement liability, end of period	$ 5,900	$ 4,900

Asset Retirement Obligation, Adjustments To Obligations Recognized

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- Definition

Asset retirement obligation gross expected future cash flows

+ References

No definition available.

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- Definition

The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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- Definition

Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6392676&loc=d3e7480-110848

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Amount of foreign currency translation gain (loss) which decreases (increases) asset retirement obligations.

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Amount of asset retirement obligations incurred during the period.

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Amount of asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset.

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

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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.

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