Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Net loss	$ (101.0)	$ (6.3)
Other comprehensive income (loss)
Foreign currency translation adjustment	0.2	0.9
Unrealized gains (losses) on available-for-sale securities	(276.0)	148.2
Disposition of subsidiary	22.8	0.0
Other comprehensive income (loss)	(253.0)	149.1
Comprehensive income (loss)	(354.0)	142.8
Comprehensive loss (income) attributable to noncontrolling interests and redeemable noncontrolling interests	(8.9)	3.2
Comprehensive income (loss) attributable to HC2 Holdings, Inc.	$ (362.9)	$ 146.0

Other Comprehensive Income (Loss), Disposal Of Subsidiary, Net of Tax

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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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