Note 13 - Pensions (Detail) - Weighted Average Assumptions	12 Months Ended
	Dec. 29, 2012	Dec. 31, 2011		Jan. 01, 2011
Expected return on plan assets	7.80%
United States Pension Plans of US Entity, Defined Benefit [Member]
Discount rate	5.40%		[1]	7.00%
Expected return on plan assets	7.80%		[2]	8.50%
Measurement dates	12/31/12	12/31/11		12/31/10
Discount rate	3.90%	5.40%			[1]
Foreign Pension Plans, Defined Benefit [Member]
Discount rate	5.50%	5.30%		5.60%
Expected return on plan assets	4.50%	4.50%		1.50%
Compensation increase rate	5.60%	5.30%		4.80%
Measurement dates	12/31/12	12/31/11		12/31/10
Discount rate	4.20%	5.50%		5.30%
Compensation increase rate	6.30%	5.60%		5.30%

[1] 5.9% used for the Littelfuse, Inc. Plan, and 5.4% used for the Cole Hersee plan.

[2] 8.5% used for the Littelfuse, inc. Plan, and 7.5% used for the Cole Hersee plan.