CONSOLIDATED CONDENSED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Income Statement [Abstract]
Net sales	$ 1,239.3	$ 1,091.5	$ 3,607.6	$ 3,222.8
Cost of goods sold	963.8	864.4	2,829.4	2,547.3
Gross profit	275.5	227.1	778.2	675.5
Selling and administrative expenses	115.2	100.7	352.1	313.2
Amortization of intangibles	16.3	5.2	47.3	15.3
Impairments	1.4	0.1	5.7	0.3
Net gain from sale of assets and businesses	(3.0)	(0.6)	(4.8)	(1.6)
Other (income) expense, net	1.5	(2.7)	(0.4)	(4.6)
Earnings before interest and income taxes	144.1	124.4	378.3	352.9
Interest expense	22.6	13.1	68.5	43.5
Interest income	1.5	2.0	5.5	6.8
Earnings before income taxes	123.0	113.3	315.3	316.2
Income taxes	23.4	23.3	68.3	63.2
Net earnings	99.6	90.0	247.0	253.0
Earnings attributable to noncontrolling interest, net of tax	0.0	0.0	0.0	(0.1)
Net earnings attributable to Leggett & Platt, Inc. common shareholders	$ 99.6	$ 90.0	$ 247.0	$ 252.9
Net earnings per share attributable to Leggett & Platt, Inc. common shareholders
Basic (in dollars per share)	$ 0.74	$ 0.67	$ 1.83	$ 1.88
Diluted (in dollars per share)	$ 0.74	$ 0.67	$ 1.83	$ 1.87
Weighted average shares outstanding
Basic (in shares)	134.9	133.8	134.7	134.4
Diluted (in shares)	135.4	134.7	135.2	135.4