Summary of Significant Accounting Policies (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Net income (loss) - numerator
Net income (loss)	$ 45,094	$ (33,261)	$ (10,309)
Less dividends to Class B shareholders - distributed earnings	0	(28)	(275)
Undistributed earnings (loss)	$ 45,094	$ (33,289)	$ (10,584)
Weighted average common shares outstanding - denominator
Weighted average common shares outstanding for basic earnings (loss) per share	58,777,000	53,957,000	42,718,000
Diluted	58,929,000	53,957,000	42,718,000
Class A [Member]
Weighted average common shares outstanding - denominator
Weighted average common shares outstanding for basic earnings (loss) per share	58,777,000	53,852,000	41,687,000
Dilutive effect of options and restricted stock units	152,000	0	0
Diluted	58,929,000	53,852,000	41,687,000
Basic
Distributed earnings (usd per share)	$ 0.00	$ 0.00	$ 0.00
Undistributed (loss) earnings (usd per share)	$ 0.77	$ (0.62)	$ (0.25)
Total (usd per share)	$ 0.77	$ (0.62)	$ (0.25)
Diluted
Distributed earnings (usd per share)	$ 0.00	$ 0.00	$ 0.00
Undistributed (loss) earnings (usd per share)	$ 0.77	$ (0.62)	$ (0.25)
Total (usd per share)	$ 0.77	$ (0.62)	$ (0.25)
Class B [Member]
Weighted average common shares outstanding - denominator
Weighted average common shares outstanding for basic earnings (loss) per share	0	105,000	1,031,000
Diluted	0	105,000	1,031,000
Basic
Distributed earnings (usd per share)	$ 0.00	$ 0.27	$ 0.27
Undistributed (loss) earnings (usd per share)	$ 0.00	$ (0.62)	$ (0.25)
Total (usd per share)	$ 0.00	$ (0.35)	$ 0.02
Diluted
Distributed earnings (usd per share)	$ 0.00	$ 0.27	$ 0.27
Undistributed (loss) earnings (usd per share)	$ 0.00	$ (0.62)	$ (0.25)
Total (usd per share)	$ 0.00	$ (0.35)	$ 0.02
Stock options [Member]
Diluted
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount		1,067,069	1,024,500
Restricted Stock Units (RSUs) [Member]
Diluted
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount		162,368	0
Restricted stock [Member]
Diluted
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount		305,807	0