Total Equity Equity II (Details) - $ / shares	Jun. 30, 2015	Dec. 31, 2014
Class Of Stock [Line Items]
Common stock par value per share (USD per share)	$ 0.01	$ 0.01
Class A Common Stock
Class Of Stock [Line Items]
Common stock, shares authorized	50,000,000	50,000,000
Common stock, shares, issued	7,200,000	7,200,000
Common stock, shares outstanding	7,200,000	7,200,000
Class B Common Stock
Class Of Stock [Line Items]
Common stock, shares authorized	150,000,000	150,000,000
Common stock, shares, issued	50,700,000	51,300,000
Common stock, shares outstanding	50,700,000	51,300,000