Condensed Consolidated Statements of Comprehensive Income (Loss) - 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 loss	$ (214.5)	$ (21.6)	$ (230.7)	$ (94.1)
Other comprehensive (loss) income
Foreign currency translation adjustment	(1.2)	(0.5)	(2.4)	3.5
Unrealized (loss) income on available-for-sale securities	0.0	65.0	(57.7)	72.8
Dispositions	(334.0)	0.0	(334.0)	22.1
Other comprehensive (loss) income	(335.2)	64.5	(394.1)	98.4
Comprehensive (loss) income	(549.7)	42.9	(624.8)	4.3
Comprehensive (loss) income attributable to noncontrolling interests and redeemable noncontrolling interests	(2.6)	(4.6)	(8.0)	2.7
Comprehensive (loss) income attributable to INNOVATE Corp.	$ (552.3)	$ 38.3	$ (632.8)	$ 7.0