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