Employee Compensation Plans - Schedule of Fair Value of Awarded Stock Option Estimated on Grant Date Using Black-Scholes Model (Details) - $ / shares		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Term granted for options (in years)	[1]	5 years	5 years	5 years	5 years	5 years
Expected volatility factor	[2]	55.43%	56.31%	53.82%	54.95%	52.52%
Risk-free interest rate	[3]	1.27%	1.49%	0.84%	0.70%	2.00%
Actual dividends (in dollars per share)	[4]	$ 0.44	$ 0.44	$ 0.44	$ 0.44	$ 0.44

[1] The expected term was determined based on actual awards.

[2] The volatility factor was measured using the weighted average of historical daily price changes of the Company's Class A Stock over a historical period commensurate to the expected term of the awards.

[3] The risk-free interest rate was based on periods equal to the expected term of the awards based on the U.S. Treasury yield curve in effect at the time of grant.

[4] Actual dividends were used to compute the expected annual dividend yield.