Consolidated Balance Sheet (Parenthetical) - $ / shares	Dec. 31, 2015	Dec. 31, 2014
Common stock, par value (USD per share)	$ 0.01	$ 0.01
Common stock, shares authorized (shares)	200,000,000	0
Common stock, shares, outstanding (shares)	57,836,533	0
Class A Common Stock
Common stock, shares authorized (shares)	0	50,000,000
Common stock, shares, outstanding (shares)	0	7,167,506
Class B Common Stock
Common stock, shares authorized (shares)	0	150,000,000
Common stock, shares, outstanding (shares)	0	51,328,974