v3.8.0.1

Organization and Summary of Significant Accounting Policies - Narrative - Concentrations of Risk (Details) |  |  | 12 Months Ended
--- | --- | --- | ---
Dec. 31, 2017 | Jan. 01, 2017 | Dec. 31, 2017 | Jan. 01, 2017 | Jan. 03, 2016
Credit concentration risk [Member] | Investment portfolio [Member] |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Maximum investment portfolio credit exposure |  |  | 5.00% |  |
Credit concentration risk [Member] | Issue size [Member] |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Maximum investment portfolio credit exposure |  |  | 5.00% |  |
Industry credit concentration risk [Member] | Investment portfolio [Member] |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Maximum investment portfolio credit exposure |  |  | 30.00% |  |
Geographic concentration risk [Member] | Sales revenue, net [Member] | Outside the United States [Member] |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Concentration percent |  |  | 45.00% | 46.00% | 46.00%
Geographic concentration risk [Member] | Accounts receivable [Member] | Outside the United States [Member] |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Concentration percent | 48.00% | 48.00% |  |  |

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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 + Details
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