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Significant Accounting Policies (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 28, 2018	May 19, 2017
Saudi Arabia-based Joint Venture
Significant Accounting Policies [Line Items]
Date of joint venture agreement	May 19, 2017
Percentage of ownership interest in joint venture		50.00%
Initial capital contributions to joint venture		$ 6.0
Minimum
Significant Accounting Policies [Line Items]
Percentage of fair value of each reporting unit in excess of book value	31.00%
Minimum | Buildings
Significant Accounting Policies [Line Items]
Estimated useful life of assets	20 years
Minimum | Equipment
Significant Accounting Policies [Line Items]
Estimated useful life of assets	3 years
Minimum | Leasehold improvements
Significant Accounting Policies [Line Items]
Estimated useful life of assets	4 years
Maximum
Significant Accounting Policies [Line Items]
Percentage of fair value of each reporting unit in excess of book value	132.00%
Maximum | Buildings
Significant Accounting Policies [Line Items]
Estimated useful life of assets	40 years
Maximum | Equipment
Significant Accounting Policies [Line Items]
Estimated useful life of assets	10 years
Maximum | Leasehold improvements
Significant Accounting Policies [Line Items]
Estimated useful life of assets	10 years

X

- Definition

Commitment By Partners For Initial Capital Contribution To Joint Venture

+ References

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- Definition

Date Of Joint Venture Agreement

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- Definition

[Line Items] for Significant Accounting Policies [Table]

+ References

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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- Definition

Percentage of fair value of reporting unit in excess of carrying amount.

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