SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 29, 2012	Sep. 29, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Oct. 01, 2011	Jul. 02, 2011	Apr. 02, 2011	Dec. 29, 2012	Dec. 31, 2011	Jan. 01, 2011
Net sales	$ 205,100	$ 237,600	$ 246,700	$ 201,900	$ 187,200	$ 224,400	$ 224,100	$ 185,400	$ 891,345	$ 821,077	$ 713,792
Gross profit	68,500	82,600	84,300	66,300	60,900	73,700	77,200	60,500	301,664	272,305	230,197
Net income	13,300	22,000	25,200	23,200	11,500	19,300	22,000	10,900	83,738	63,723	39,918
Net Income attributable to Franklin Electric Co., Inc.	$ 13,200	$ 21,900	$ 24,800	$ 23,000	$ 11,500	$ 19,200	$ 21,700	$ 10,700	$ 82,864	$ 63,099	$ 38,914
Basic earnings per share (in dollars per share)	$ 0.55	$ 0.93	$ 1.06	$ 0.99	$ 0.51	$ 0.82	$ 0.92	$ 0.46	$ 3.52	$ 2.71	$ 1.68
Diluted earnings per share (in dollars per share)	$ 0.55	$ 0.91	$ 1.04	$ 0.96	$ 0.50	$ 0.80	$ 0.91	$ 0.45	$ 3.46	$ 2.65	$ 1.65