Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (36.1)	$ 179.9
Other comprehensive income (loss)
Foreign currency translation adjustment	(1.9)	4.1
Unrealized gains (losses) on available-for-sale securities	288.4	(158.2)
Actuarial loss on pension plan	(7.8)	(6.7)
Other comprehensive income (loss)	278.7	(160.8)
Comprehensive income	242.6	19.1
Comprehensive income attributable to noncontrolling interests and redeemable noncontrolling interests	(7.5)	(15.1)
Comprehensive income attributable to HC2 Holdings, Inc.	$ 235.1	$ 4.0

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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