Summary of Significant Accounting Policies (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Net income (loss) - numerator
Net (loss) income	$ 18,226	$ 25,119	$ 34,589	$ 9,615
Weighted average common shares outstanding - denominator
Weighted average common shares outstanding for basic earnings (loss) per share	68,531	55,839	67,108	55,729
Dilutive effect of options and restricted stock units	689	98	663	90
Weighted average common shares outstanding - Diluted	69,220	55,937	67,771	55,819