CONSOLIDATED CONDENSED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Income Statement [Abstract]
Net trade sales	$ 1,207.6	$ 1,239.3	$ 3,098.2	$ 3,607.6
Cost of goods sold	940.8	963.8	2,462.3	2,829.4
Gross profit	266.8	275.5	635.9	778.2
Selling and administrative expenses	105.6	115.2	320.6	352.1
Amortization of intangibles	16.2	16.3	48.9	47.3
Impairments	0.0	1.4	29.4	5.7
Net gain from sale of assets and businesses	(2.1)	(3.0)	(2.5)	(4.8)
Other (income) expense, net	(0.2)	1.5	(11.3)	(0.4)
Earnings before interest and income taxes	147.3	144.1	250.8	378.3
Interest expense	20.9	22.6	63.2	68.5
Interest income	0.5	1.5	2.4	5.5
Earnings before income taxes	126.9	123.0	190.0	315.3
Income taxes	22.0	23.4	45.5	68.3
Net earnings	104.9	99.6	144.5	247.0
(Earnings) attributable to noncontrolling interest, net of tax	(0.1)	0.0	(0.1)	0.0
Net earnings attributable to Leggett & Platt, Inc. common shareholders	$ 104.8	$ 99.6	$ 144.4	$ 247.0
Net earnings per share attributable to Leggett & Platt, Inc. common shareholders
Basic (in dollars per share)	$ 0.77	$ 0.74	$ 1.06	$ 1.83
Diluted (in dollars per share)	$ 0.77	$ 0.74	$ 1.06	$ 1.83
Weighted average shares outstanding
Basic (in shares)	135.8	134.9	135.6	134.7
Diluted (in shares)	136.1	135.4	135.8	135.2