Earnings per Share (Tables)

6 Months Ended

Jun. 30, 2012

Earnings Per Share [Abstract]

Schedule of calculation of basic and diluted earnings per share

The following table sets forth the calculations of basic and diluted earnings per share:

	For the Three Months Ended June 30,				For the Six Months Ended June 30,
	2012		2011		2012		2011
	(in thousands, except per share amounts)
Net income	$	24,889	$	124,533	$	51,225	$	106,030
Basic weighted-average common shares outstanding	64,585		63,638		64,345		63,543
Add: dilutive effect of stock options, unvested RSUs, and contingent PSUs	2,149		2,182		2,182		2,161
Add: dilutive effect of 3.50% Senior Convertible Notes	822		1,089		1,279		991
Diluted weighted-average common shares outstanding	67,556		66,909		67,806		66,695
Basic net income per common share	$	0.39	$	1.96	$	0.80	$	1.67
Diluted net income per common share	$	0.37	$	1.86	$	0.76	$	1.59