Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions		Jun. 30, 2018	Dec. 31, 2017
Assets
Cash and cash equivalents		$ 35.0	$ 69.8
Investments, at fair value		1,200.7	655.0
Other receivables		69.5	21.7
Total assets	[1]	1,305.2	746.5
Liabilities
Collateralized loan obligation notes, at fair value		941.2	450.7
Other liabilities		145.3	122.7
Total liabilities	[1]	1,086.5	573.4
Fixed maturity securities available for sale, amortized cost		10,777.0	8,756.5
Equity securities, cost		$ 349.6
Equity securities available for sale, cost			$ 316.3
Preferred stock, par value (in dollars per share)		$ 1.00
Preferred stock, shares authorized (in shares)		2,875,000
Preferred stock, shares issued (in shares)		2,875,000
Preferred stock, shares outstanding (in shares)		2,875,000
Common stock, par value (in dollars per share)		$ 0.01	$ 0.01
Common stock, shares authorized (in shares)		800,000,000	800,000,000
Common Stock, Shares, Issued		161,069,104	150,392,604
Common stock, shares outstanding (in shares)		63,094,312	52,417,812
Treasury stock, at cost (in shares)		97,974,792	97,974,792

[1] The following table presents information on assets and liabilities related to consolidated investment entities as of June 30, 2018 and December 31, 2017