CONSOLIDATED CONDENSED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement of Comprehensive Income [Abstract]
Net earnings	$ 97.2	$ 107.1	$ 297.0	$ 145.1
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	(15.7)	26.0	(16.5)	(13.7)
Cash flow hedges	8.3	3.4	10.5	0.8
Defined benefit pension plans	1.0	0.4	2.7	2.2
Other comprehensive income (loss)	(6.4)	29.8	(3.3)	(10.7)
Comprehensive income (loss)	90.8	136.9	293.7	134.4
Add: comprehensive (income) attributable to noncontrolling interest	0.0	(0.1)	(0.1)	0.0
Comprehensive income (loss) attributable to Leggett & Platt, Inc.	$ 90.8	$ 136.8	$ 293.6	$ 134.4