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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 |

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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 + Details
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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. + References No definition available. + Details
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