Note 19 - Enterprise-wide Disclosures - Operating Segments (Details) - USD ($) $ in Thousands	3 Months Ended													12 Months Ended
	Dec. 30, 2018		Sep. 30, 2018	[2]	Jul. 01, 2018	[3]	Apr. 01, 2018	Dec. 31, 2017		Oct. 01, 2017	Jul. 02, 2017	Apr. 02, 2017	[5]	Dec. 30, 2018		Dec. 31, 2017		Jan. 01, 2017
Net Sales	$ 337,059	[1]	$ 318,325		$ 283,626		$ 240,563	$ 266,210	[4]	$ 257,431	$ 251,700	$ 221,102		$ 1,179,573	[6]	$ 996,443	[6]	$ 958,617	[6]
Depreciation and amortization														39,084		30,261		30,632
Total assets	1,284,644							800,600						1,284,644		800,600
Operating Segments [Member]
Net Sales														1,179,573		996,443		958,617
Depreciation and amortization														35,161		28,259		29,066
Total assets	1,229,952							719,957						1,229,952		719,957
Americas [Member] | Operating Segments [Member]
Net Sales														682,261		588,052		568,138
Depreciation and amortization														13,732		13,548		14,639
Total assets	482,510							272,883						482,510		272,883
Europe [Member] | Operating Segments [Member]
Net Sales														319,677		246,399		241,463
Depreciation and amortization														12,862		6,049		5,698
Total assets	546,758							253,519						546,758		253,519
Asia Pacific [Member] | Operating Segments [Member]
Net Sales														177,635		161,992		149,016
Depreciation and amortization														8,567		8,662		$ 8,729
Total assets	$ 200,684							$ 193,555						$ 200,684		$ 193,555

[1] Results for the fourth quarter of 2018 include tax benefit of $6.7 million as a result of the finalization of the Company's analysis of the U.S. Tax Cuts and Jobs Act, as well as restructuring and asset impairment charges of $20.5 million. Results for the fourth quarter of 2018 include purchase price accounting amortization of $11.8 million and transaction related expense of $1.2 million.

[2] Results for the third quarter of 2018 include purchase price accounting amortization of $20.3 million and transaction related expenses of $2.4 million.

[3] Results for the second quarter of 2018 include transaction related expenses of $5.8 million.

[4] Results for the fourth quarter of 2017 include tax charges of $15.2 million as a result of the U.S. Tax Cuts and Jobs Act.

[5] Results for the first quarter of 2017 include restructuring and asset impairment charges of $7.3 million.

[6] Revenue attributed to geographic areas is based on the location of the customer.