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Note 15 - Employee Benefit Plans - Funded Status of Defined Benefit Plans (Details) - USD ($) $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2017 | Jan. 01, 2017 | Jan. 03, 2016 | Dec. 31, 2017 | Jan. 01, 2017
Amounts recognized in accumulated other comprehensive income (after tax) |  |  |  |  |
Total amount recognized |  |  |  | $ 56,554 | $ 54,862
UNITED STATES |  |  |  |  |
Change in benefit obligation |  |  |  |  |
Benefit obligation, beginning of year | $ 29,700 | $ 25,860 |  |  |
Service cost | 0 | 440 | $ 594 |  |
Interest cost | 1,256 | 1,269 | 1,113 |  |
Benefits and expenses paid | (1,943) | (1,012) |  |  |
Actuarial loss (gain) | 2,906 | 3,143 |  |  |
Benefit obligation, end of year | 31,919 | 29,700 | 25,860 |  |
Current liabilities |  |  |  | 2,030 | 1,890
Non-current liabilities |  |  |  | 29,889 | 27,810
Total benefit obligation |  |  |  | 31,919 | 29,700
Unrecognized actuarial loss |  |  |  | 8,582 | 5,626
Change in plan assets |  |  |  |  |
Company contributions | 1,900 |  |  |  |
Amounts recognized in accumulated other comprehensive income (after tax) |  |  |  |  |
Unrecognized actuarial loss |  |  |  | 8,582 | 5,626
Accumulated Benefit Obligation |  |  |  | 31,900 | 29,700
Projected Benefit Obligation | 29,700 | 29,700 | 25,860 | 31,919 | 29,700
Foreign Plan [Member] |  |  |  |  |
Change in benefit obligation |  |  |  |  |
Benefit obligation, beginning of year | 277,813 | 243,717 |  |  |
Service cost | 1,628 | 1,032 | 1,061 |  |
Interest cost | 5,559 | 6,580 | 8,384 |  |
Benefits and expenses paid | (10,267) | (8,551) |  |  |
Actuarial loss (gain) | 13,351 | 73,600 |  |  |
Member contributions | 262 | 225 |  |  |
Currency translation adjustment | 32,202 | (38,790) |  |  |
Benefit obligation, end of year | 320,548 | 277,813 | 243,717 |  |
Unrecognized actuarial loss |  |  |  | 48,443 | 49,547
Change in plan assets |  |  |  |  |
Plan assets, beginning of year | 258,365 | 239,281 |  |  |
Actuarial gain (loss) | 25,691 | 59,364 |  |  |
Company contributions | 2,812 | 4,991 |  |  |
Benefits paid | (10,267) | (8,552) |  |  |
Translation adjustment | 30,565 | (36,719) |  |  |
Plan assets, end of year | 307,166 | 258,365 | 239,281 |  |
Reconciliation to balance sheet |  |  |  |  |
Funded status benefit asset/(liability) |  |  |  | (13,382) | (19,448)
Net amount recognized |  |  |  | (13,382) | (19,448)
Amounts recognized in accumulated other comprehensive income (after tax) |  |  |  |  |
Unrecognized actuarial loss |  |  |  | 48,443 | 49,547
Unamortized prior service costs |  |  |  | (471) | (311)
Total amount recognized |  |  |  | 47,972 | 49,236
Accumulated Benefit Obligation |  |  |  | 313,257 | 274,414
Projected Benefit Obligation | 277,813 | 277,813 | $ 243,717 | 320,548 | 277,813
Foreign Plan [Member] | Uk Plan [Member] |  |  |  |  |
Change in benefit obligation |  |  |  |  |
Benefit obligation, beginning of year | 171,172 |  |  |  |
Benefit obligation, end of year | 190,992 | 171,172 |  |  |
Change in plan assets |  |  |  |  |
Plan assets, beginning of year | 153,132 |  |  |  |
Plan assets, end of year | 179,322 | 153,132 |  |  |
Amounts recognized in accumulated other comprehensive income (after tax) |  |  |  |  |
Accumulated Benefit Obligation |  |  |  | 190,992 | 171,172
Projected Benefit Obligation | 190,992 | 171,172 |  | 190,992 | 171,172
Plan Assets |  |  |  | 179,322 | 153,132
Foreign Plan [Member] | Dutch Plan [Member] |  |  |  |  |
Change in benefit obligation |  |  |  |  |
Benefit obligation, beginning of year | 106,641 |  |  |  |
Benefit obligation, end of year | 129,554 | 106,641 |  |  |
Change in plan assets |  |  |  |  |
Plan assets, beginning of year | 105,233 |  |  |  |
Plan assets, end of year | 127,844 | 105,233 |  |  |
Amounts recognized in accumulated other comprehensive income (after tax) |  |  |  |  |
Accumulated Benefit Obligation |  |  |  | 122,265 | 103,242
Projected Benefit Obligation | $ 129,554 | $ 106,641 |  | 129,554 | 106,641
Plan Assets |  |  |  | $ 127,844 | $ 105,233

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- Definition Amount, after tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (i-k) -URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669646-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669686-108580 + Details
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- Definition Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level. + 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 (e) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount, after tax, of accumulated other comprehensive (income) loss for cost (credit) of benefit change attributable to participants' prior service from plan amendment or plan initiation of defined benefit plan, that has not been recognized in net periodic benefit cost (credit). + 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 (j) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669686-108580 + Details
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- Definition Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses. + 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)(1) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(6) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of foreign currency translation gain (loss) which (increases) decreases benefit obligation of defined benefit 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 (a)(5) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status. + 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 (c) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=64852052&loc=d3e1703-114919 + Details
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