Quarterly Financial Data (unaudited) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Net sales	$ 871.3	$ 821.0	$ 722.8	$ 690.9	$ 676.1	$ 729.5	$ 659.9	$ 637.4	$ 3,106.0	$ 2,702.9	$ 2,700.6
Gross profit	386.4	360.6	313.4	281.8	283.2	300.0	272.8	264.7	1,342.2	1,120.7	1,121.0
Operating income	84.6	120.6	81.0	60.5	57.9	84.7	58.0	55.7	346.7	256.3	295.5
Income from continuing operations	46.7	72.4	42.7	29.0	19.1	44.1	26.6	25.6	190.9	118.3	182.3
Net income attributable to Tempur Sealy International, Inc.	$ 46.2	$ 73.3	$ 41.6	$ 28.4	$ 12.3	$ 42.3	$ 22.8	$ 23.1	$ 189.5	$ 100.5	$ 151.4
Earnings per share for continuing operations, basic (in dollars per share)	$ 0.87	$ 1.33	$ 0.78	$ 0.53	$ 0.35	$ 0.83	$ 0.52	$ 0.48	$ 3.50	$ 2.17	$ 3.37
Earnings per share for continuing operations, diluted (in dollars per share)	$ 0.85	$ 1.30	$ 0.76	$ 0.52	$ 0.35	$ 0.82	$ 0.52	$ 0.47	$ 3.45	$ 2.15	$ 3.33