Basis of Presentation, Significant Accounting Policies, and Recently Issued Accounting Standards Earnings Per Share (Tables)

12 Months Ended

Dec. 31, 2011

Earnings Per Share Reconciliation [Abstract]

Dilutive and Anti-Dilutive Shares for Stock Based Compensation [Table Text Block]

	For the Years Ended December 31,
	2011	2010	2009
Dilutive	3,808,589	1,720,149	—
Anti-dilutive	—	—	1,152,127

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

	For the Years Ended December 31,
	2011		2010		2009
	(in thousands, except per share amounts)
Net income (loss)	$	215,416	$	196,837	$	(99,370	)
Basic weighted-average common shares outstanding	63,755		62,969		62,457
Add: dilutive effect of stock options, unvested RSUs, and contingent PSUs	2,592		1,720		—
Add: dilutive effect of 3.50% Senior Convertible Notes	1,217		—		—
Diluted weighted-average common shares outstanding	67,564		64,689		62,457
Basic net income (loss) per common share	$	3.38	$	3.13	$	(1.59	)
Diluted net income (loss) per common share	$	3.19	$	3.04	$	(1.59	)