Condensed Consolidated Balance Sheets (unaudited) (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Investments	$ 1,120.4	$ 1,174.8
Class A
Common stock, nominal value (in dollars per share)	$ 0.01	$ 0.01
Common stock, issued (in shares)	181,068,554	204,450,499
Common stock, outstanding (in shares)	181,068,554	204,450,499
Class B
Common stock, nominal value (in dollars per share)	$ 0.01	$ 0.01
Common stock, issued (in shares)	12,157,826	11,099,593
Common stock, outstanding (in shares)	12,157,826	11,099,593
Class C
Common stock, nominal value (in dollars per share)	$ 0.01	$ 0.01
Common stock, issued (in shares)	437,877,905	531,174,389
Common stock, outstanding (in shares)	437,877,905	531,174,389

Face amount or stated value per share of common stock.

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