CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Jan. 02, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 78,593	$ 79,315	$ 73,691
Other comprehensive income/(loss), before tax:
Foreign currency translation adjustments	17,937	(8,459)	(58,886)
Employee benefit plan activity:
Net gain/(loss) arising during period	(274)	(3,809)	1,278
Amortization arising during period	3,012	4,298	5,759
Other comprehensive income/(loss)	20,675	(7,970)	(51,849)
Income tax expense related to items of other comprehensive income/(loss)	(534)	(499)	(2,471)
Other comprehensive income/(loss), net of tax	20,141	(8,469)	(54,320)
Comprehensive income	98,734	70,846	19,371
Less: Comprehensive income/(loss) attributable to noncontrolling interests	(251)	345	121
Comprehensive income attributable to Franklin Electric Co., Inc.	$ 98,985	$ 70,501	$ 19,250