Note 8 - Benefit Plans - Benefit Plan Related Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 30, 2017	Dec. 31, 2016	Jan. 02, 2016
Change in benefit obligation:
Service cost	$ 2,037	$ 1,509	$ 1,574
Interest cost	1,887	1,662	4,828
Change in plan assets at fair value:
Fair value of plan assets at beginning of year	42,208
Fair value of plan assets at end of year	48,123	42,208
Amounts recognized in the Consolidated Balance Sheets consist of:
Noncurrent benefit liability	(18,742)	(13,398)
Pension Plan [Member]
Change in benefit obligation:
Benefit obligation at beginning of year	55,606	50,282
Service cost	2,037	1,509
Interest cost	1,887	1,662
Net actuarial loss (gain)	(433)	10,190
Benefits paid from the trust	(1,405)	(2,329)
Benefits paid directly by the Company	(1,098)	250
Curtailments and settlements	(31)	(427)
Acquisitions		2,023
Effect of exchange rate movements	5,477	(7,554)
Other	5,228
Benefit obligation at end of year	67,268	55,606	50,282
Change in plan assets at fair value:
Fair value of plan assets at beginning of year	42,208	44,629
Actual return on plan assets	2,962	6,929
Employer contributions	264
Employer contributions		(126)
Benefits paid	(1,405)	(2,329)
Acquisitions		24
Effect of exchange rate movements	4,094	(6,919)
Fair value of plan assets at end of year	48,123	42,208	$ 44,629
Net amount recognized/(unfunded status)	(19,145)	(13,398)
Amounts recognized in the Consolidated Balance Sheets consist of:
Noncurrent assets	78
Current benefit liability	(481)
Noncurrent benefit liability	(18,742)	(13,398)
Net liability recognized	$ (19,145)	$ (13,398)