Earnings per Share (Tables)

9 Months Ended

Sep. 30, 2015

Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]

The following table sets forth the computation of basic and diluted earnings per common share for the three and nine months ended September 30, 2015 and 2014 (in thousands, except per share amounts):



	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2015		2014		2015		2014
Numerator:
Net income	$	63,362	$	72,650	$	140,103	$	173,382
Denominators:
Weighted average Class A common shares outstanding - Basic	56,819		55,600		56,673		55,167
Weighted average Class B common shares outstanding	828		1,059		915		1,394
Dilutive effect of employee stock-based awards	199		355		245		382
Weighted average shares - Diluted	57,846		57,014		57,833		56,943

Basic earnings per common share	$	1.12	$	1.31	$	2.47	$	3.14
Diluted earnings per common share	$	1.10	$	1.27	$	2.42	$	3.05

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]

The following total number of Class A Common Stock shares issuable under the assumed exercise of stock-based awards computed based on the treasury stock method were excluded from the calculation of diluted earnings per common share, as the effect of including these shares would have been antidilutive (in thousands):



	Three Months Ended		Nine Months Ended
	September 30,		September 30,
	2015	2014	2015	2014
Antidilutive shares	772	293	652	259