The following table sets forth the computation of basic and diluted earnings per share under the two-class method:


	Three months ended						Six months ended
	June 30,						June 30,
	2012			2011			2012			2011
Numerator for basic and diluted earnings per share:
Net income	$	31,917		$	29,944		$	62,208		$	60,108
Effect of reallocating undistributed earnings of participating securities		(171	)		(174	)		(336	)		(350	)

Net income available under the two-class method	$	31,746		$	29,770		$	61,872		$	59,758

Denominator:
Denominator for basic earnings per share— weighted-average shares		22,961,130			23,027,104			22,967,558			23,020,851
Effect of dilutive securities:
Employee stock options		1,220			1,346			1,250			1,324

Dilutive potential common shares		1,220			1,346			1,250			1,324

Denominator for diluted earnings per share— adjusted weighted-average shares		22,962,350			23,028,450			22,968,808			23,022,175

Basic earnings per share	$	1.38		$	1.29		$	2.69		$	2.60

Diluted earnings per share	$	1.38		$	1.29		$	2.69		$	2.60