Earnings Per Share (Tables)

9 Months Ended

Sep. 30, 2013

Earnings Per Share [Abstract]

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

		Three Months Ended				Nine Months Ended
		September 30,				September 30,
		2013		2012		2013		2012
BASIC
Weighted average number of common shares outstanding
used in computing basic earnings per share		46,605		45,997		46,260		45,702
Net income attributable to common stockholders	$	13,619	$	8,553	$	20,328	$	20,077
Earnings per share attributable to common stockholders	$	0.29	$	0.19	$	0.44	$	0.44
DILUTED
Weighted average number of common shares outstanding
used in computing basic earnings per share		46,605		45,997		46,260		45,702
Add: Assumed exercise of stock options and stock awards		1,418		998		1,324		1,199
		48,023		46,995		47,584		46,901
Net income attributable to common stockholders	$	13,619	$	8,553	$	20,328	$	20,077
Earnings per share attributable to common stockholders	$	0.28	$	0.18	$	0.43	$	0.43