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Note 15 - Employee Benefit Plans (Details) - Weighted Average Asset Allocations | 12 Months Ended |
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Jan. 03, 2016 | Dec. 28, 2014
Asset Category: |  |
Target allocation | 100.00% |
Percentage of plan assets at year end | 100.00% | 100.00%
Equity Securities [Member] |  |
Asset Category: |  |
Percentage of plan assets at year end | 49.00% | 63.00%
Debt Securities [Member] |  |
Asset Category: |  |
Percentage of plan assets at year end | 41.00% | 34.00%
Other Securities [Member] |  |
Asset Category: |  |
Percentage of plan assets at year end | 10.00% | 3.00%
Minimum [Member] | Equity Securities [Member] |  |
Asset Category: |  |
Target allocation | 45.00% |
Minimum [Member] | Debt Securities [Member] |  |
Asset Category: |  |
Target allocation | 35.00% |
Minimum [Member] | Other Securities [Member] |  |
Asset Category: |  |
Target allocation | 0.00% |
Maximum [Member] | Equity Securities [Member] |  |
Asset Category: |  |
Target allocation | 55.00% |
Maximum [Member] | Debt Securities [Member] |  |
Asset Category: |  |
Target allocation | 45.00% |
Maximum [Member] | Other Securities [Member] |  |
Asset Category: |  |
Target allocation | 10.00% |

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- Definition Target allocation of investments of this type to total plan assets presented on a weighted average basis. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (c)(i) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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- Definition Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(1) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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