SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Jan. 03, 2015	Sep. 27, 2014	Jun. 28, 2014	Mar. 29, 2014	Dec. 28, 2013	Sep. 28, 2013	Jun. 29, 2013	Mar. 30, 2013	Jan. 03, 2015	Dec. 28, 2013	Dec. 29, 2012
Net sales	$ 253,800	$ 278,100	$ 284,500	$ 231,400	$ 229,800	$ 249,800	$ 263,400	$ 222,500	$ 1,047,777	$ 965,462	$ 891,345
Gross profit	77,700	89,200	99,400	78,100	76,000	87,000	94,600	73,900	344,410	331,514	301,664
Net income	3,200	22,800	27,500	17,400	13,400	25,300	28,400	15,600	70,852	82,698	83,738
Net income attributable to Franklin Electric Co., Inc.	$ 3,000	$ 22,700	$ 27,100	$ 17,000	$ 13,300	$ 25,100	$ 28,100	$ 15,500	$ 69,806	$ 81,958	$ 82,864
Basic earnings per share (in dollars per share)	$ 0.06	$ 0.46	$ 0.56	$ 0.35	$ 0.27	$ 0.52	$ 0.59	$ 0.32	$ 1.43	$ 1.70	$ 1.76
Diluted earnings per share (in dollars per share)	$ 0.06	$ 0.46	$ 0.55	$ 0.35	$ 0.27	$ 0.51	$ 0.58	$ 0.32	$ 1.41	$ 1.68	$ 1.73