Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions		Sep. 30, 2018	Dec. 31, 2017
Assets
Cash and cash equivalents		$ 125.3	$ 69.8
Investments, at fair value		1,450.9	655.0
Other receivables		23.3	21.7
Total assets	[1]	1,599.5	746.5
Liabilities
Collateralized loan obligation notes, at fair value		1,177.7	450.7
Other liabilities		196.5	122.7
Total liabilities	[1]	1,374.2	573.4
Fixed maturity securities available for sale, amortized cost		10,669.2	8,756.5
Equity securities, cost		$ 349.3
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		161,134,668	150,392,604
Common stock, shares outstanding (in shares)		62,376,266	52,417,812
Treasury stock, at cost (in shares)		98,758,402	97,974,792

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