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Note 15 - Employee Benefit Plans - Assets at Fair Value (Details) - Foreign Plan [Member] - USD ($) $ in Thousands | Dec. 31, 2017 | Jan. 01, 2017 | Jan. 03, 2016
--- | --- | --- | ---
Asset Category: |  |  |
Percentage of Plan Assets at Year End | 100.00% | 100.00% |
Assets at fair value | $ 307,166 | $ 258,365 | $ 239,281
Dutch Plan [Member] |  |  |
Asset Category: |  |  |
Assets at fair value | 127,844 | 105,233 |
Uk Plan [Member] |  |  |
Asset Category: |  |  |
Assets at fair value | 179,322 | 153,132 |
Fair Value, Inputs, Level 1 [Member] |  |  |
Asset Category: |  |  |
Assets at fair value | 87,521 | 80,048 |
Fair Value, Inputs, Level 1 [Member] | Dutch Plan [Member] |  |  |
Asset Category: |  |  |
Assets at fair value | 0 | 0 |
Fair Value, Inputs, Level 1 [Member] | Uk Plan [Member] |  |  |
Asset Category: |  |  |
Assets at fair value | 87,521 | 80,048 |
Fair Value, Inputs, Level 2 [Member] |  |  |
Asset Category: |  |  |
Assets at fair value | 68,668 | 50,364 |
Fair Value, Inputs, Level 2 [Member] | Dutch Plan [Member] |  |  |
Asset Category: |  |  |
Assets at fair value | 0 | 0 |
Fair Value, Inputs, Level 2 [Member] | Uk Plan [Member] |  |  |
Asset Category: |  |  |
Assets at fair value | 68,668 | 50,364 |
Fair Value, Inputs, Level 3 [Member] |  |  |
Asset Category: |  |  |
Assets at fair value | 150,977 | 127,953 |
Fair Value, Inputs, Level 3 [Member] | Dutch Plan [Member] |  |  |
Asset Category: |  |  |
Assets at fair value | 127,844 | 105,233 |
Fair Value, Inputs, Level 3 [Member] | Uk Plan [Member] |  |  |
Asset Category: |  |  |
Assets at fair value | $ 23,133 | $ 22,720 |
Maximum [Member] |  |  |
Asset Category: |  |  |
Target Allocation | 100.00% |  |
Equity Securities [Member] |  |  |
Asset Category: |  |  |
Target Allocation | 20.00% |  |
Percentage of Plan Assets at Year End | 16.00% | 15.00% |
Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |
Asset Category: |  |  |
Assets at fair value | $ 48,285 | $ 37,696 |
Equity Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |
Asset Category: |  |  |
Assets at fair value | 0 | 0 |
Equity Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Asset Category: |  |  |
Assets at fair value | $ 0 | $ 0 |
Equity Securities [Member] | Minimum [Member] |  |  |
Asset Category: |  |  |
Target Allocation | 15.00% |  |
Debt Securities [Member] |  |  |
Asset Category: |  |  |
Target Allocation | 45.00% |  |
Percentage of Plan Assets at Year End | 32.00% | 36.00% |
Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |
Asset Category: |  |  |
Assets at fair value | $ 36,780 | $ 37,175 |
Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |
Asset Category: |  |  |
Assets at fair value | 41,381 | 36,378 |
Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Asset Category: |  |  |
Assets at fair value | $ 19,883 | $ 19,224 |
Debt Securities [Member] | Minimum [Member] |  |  |
Asset Category: |  |  |
Target Allocation | 35.00% |  |
Other Securities [Member] |  |  |
Asset Category: |  |  |
Target Allocation | 50.00% |  |
Percentage of Plan Assets at Year End | 52.00% | 49.00% |
Other Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |
Asset Category: |  |  |
Assets at fair value | $ 2,456 | $ 5,177 |
Other Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |
Asset Category: |  |  |
Assets at fair value | 27,287 | 13,986 |
Other Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Asset Category: |  |  |
Assets at fair value | $ 131,094 | $ 108,729 |
Other Securities [Member] | Minimum [Member] |  |  |
Asset Category: |  |  |
Target Allocation | 40.00% |  |
Other Securities [Member] | Maximum [Member] |  |  |
Asset Category: |  |  |
Target Allocation |  |  |

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- Definition Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(5)(i) -URI http://asc.fasb.org/extlink&oid=82843861&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=82843861&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=82843861&loc=d3e1928-114920 + Details
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