Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2012

Summary of Significant Accounting Policies [Abstract]

Schedule of Weighted Average Number of Shares [Table Text Block]

	Years Ended December 31,
	2012	2011	2010
Basic weighted average shares outstanding	70,374,000	69,283,000	69,161,000
Effect of dilution:
Stock options	783,000	510,000	—
Restricted shares/units	1,079,000	938,000	—
Diluted weighted average shares outstanding	72,236,000	70,731,000	69,161,000

Schedule of Stock by Class [Table Text Block]

	Shares Outstanding
	Class A  Common Stock	Class B  Common Stock
Balance at June 30, 2011 (date of Distribution)	57,813,267	13,534,408
Employee and non-employee director stock transactions*	621,437	—
Balance at December 31, 2011	58,434,704	13,534,408
Conversion of Class B common stock to Class A common stock	1,750,000	(1,750,000	)
Employee and non-employee director stock transactions*	406,326	—
Balance at December 31, 2012	60,591,030	11,784,408

*Primarily includes issuances of common stock in connection with employee stock option exercises and restricted shares/units granted to employees, partially offset by shares acquired by the Company in connection with the fulfillment of employees’ statutory tax withholding obligations for applicable income and other employment taxes and forfeited employee restricted shares.