Earnings Per Share

9 Months Ended

Sep. 30, 2011

Earnings Per Share [Abstract]

Earnings Per Share

Note 2: Earnings per Share

Basic earnings per share is calculated by dividing net earnings available to common stockholders by the weighted average number of shares of common stock outstanding during the period. Diluted earnings per share is calculated on the basis of the weighted average number of shares of common stock plus the effect of dilutive potential common shares outstanding during the period using the treasury stock method. Dilutive potential common shares include outstanding stock options and restricted stock units.

The components of basic and diluted earnings per share are as follows (in thousands, except earnings per share):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2011		2010		2011		2010
Net income available for common stockholders (A)	$	15,370	$	12,290	$	43,824	$	34,881
Weighted average outstanding shares of common stock (B)		24,638		23,947		24,493		23,793
Dilutive effect of stock-based awards		966		1,207		1,143		1,219
Common stock and common stock equivalents (C)		25,604		25,154		25,636		25,012
Earnings per share:
Basic (A/B)	$	0.62	$	0.51	$	1.79	$	1.47
Diluted (A/C)	$	0.60	$	0.49	$	1.71	$	1.39

Employee stock options to purchase approximately 209,000 and 153,000 shares of common stock during the three and nine months ended September 30, 2011, respectively, and employee stock options to purchase approximately 199,000 and 219,000 shares of common stock during the three and nine months ended September 30, 2010, were outstanding but not included in the computation of diluted earnings per share because the effect on diluted earnings per share would be anti-dilutive.