Earnings Per Share (Tables)

6 Months Ended

Jun. 30, 2012

Earnings Per Share [Abstract]

Computation of earnings per share and reconciliation of basic and diluted weighted average common shares outstanding

The table below presents the computation of earnings per share, including the reconciliation of basic and diluted weighted average shares outstanding (in thousands, except EPS):

			Three Months Ended June 30,				Six Months Ended June 30,
			2012		2011		2012		2011
Net income			$	64,943	$	58,577	$	68,594	$	57,939
Weighted average shares outstanding:
	Basic			47,142		48,231		47,330		48,546
	Effect of dilutive securities:
		Stock options and employee stock purchase plan		1,146		885		1,100		806
	Diluted			48,288		49,116		48,430		49,352
Earnings per share:
	Basic		$	1.38	$	1.21	$	1.45	$	1.19
	Diluted		$	1.34	$	1.19	$	1.42	$	1.17
Anti-dilutive stock options excluded from diluted earnings per share computations				991		1,384		1,174		1,420