Earnings Per Common Share Common Stock (Details)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Class A Common Stock, $0.01 par value, one vote per share; 180,000,000 shares authorized at December 31, 2015 and 2014; 69,674,185 and 65,632,309 shares issued and 56,945,384 and 52,938,267 shares outstanding (net of 12,728,801 and 12,694,042 shares in treasury) on December 31, 2015 and 2014, respectively
Common Stock, Voting Rights	1	1
Class B Common Stock [Member]
Common Stock, Voting Rights	10	10