Note 8 - Shareholders' Equity (Tables)

3 Months Ended

Mar. 31, 2018

Notes Tables

Schedule of Stockholders Equity [Table Text Block]

(in thousands )	Littelfuse, Inc. Shareholders’ Equity			Non- controlling Interest		Total
Balance at December 30, 2017	$	927,419		$	137	$	927,556
Net income		36,029			—		36,029
Other comprehensive income		(279	)		—		(279	)
Stock-based compensation		8,714			—		8,714
Withheld shares on restricted share units for withholding taxes		(2,758	)		—		(2,758	)
Stock options exercised		9,609			—		9,609
Issuance of common stock (a)		472,301			—		472,301
Cash dividends paid ($0.37 per share)		(9,198	)		—		(9,198	)
Non-controlling interest		—			—		—
Balance at March 31, 2018	$	1,441,837		$	137	$	1,441,974

Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]

(in thousands )	Pension and postretirement liability and reclassification adjustments (a)			Unrealized g ain /(loss) on investments			Foreign currency translation adjustment			Accumulated other comprehensive income (loss)
Balance at December 30, 2017	$	(10,836	)	$	9,795		$	(62,627	)	$	(63,668	)
Cumulative effect adjustment (b)		—			(9,795	)		—			(9,795	)
Activity in the period		(3	)		—			(276	)		(279	)
Balance at March 31, 2018	$	(10,839	)	$	—		$	(62,903	)	$	(73,742	)