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Consolidated Statement of Changes in Stockholders / Members Equity (USD $) In Thousands | Total | Capital Contributions [Member] | Common Stock [Member] | Treasury Stock [Member] | Additional Paid-in Capital [Member] | Retained Deficit/Accumulated Loss [Member]
--- | --- | --- | --- | --- | --- | ---
Balance at Dec. 31, 2009 | $ 171,850 | $ 235,000 |  |  |  | $ (63,150)
Balance, shares at Dec. 31, 2009 |  |  |  |  |  |
Issuance of common stock | 920 |  | 920 |  |  |
Issuance of common stock, shares |  |  | 92,000 |  |  |
Proceeds from the sale of common stock | 398,749 |  |  |  | 398,749 |
Reclassification of members' contributions |  | (235,000) |  |  | 235,000 |
Stock-based compensation | 9,970 |  |  |  | 9,970 |
Stock-based compensation, shares |  |  | 240 |  |  |
Net income (loss) | (29,695) |  |  |  |  | (29,695)
Balance at Dec. 31, 2010 | 551,794 |  | 920 |  | 643,719 | (92,845)
Balance, shares at Dec. 31, 2010 |  |  | 92,240 |  |  |
Stock-based compensation | 3,656 |  |  |  | 3,656 |
Stock-based compensation, shares |  |  | 243 |  |  |
Vesting of restricted shares |  |  | 1 |  | (1) |
Treasury stock - tax withholdings | (602) |  |  | (602) |  |
Treasury stock - tax withholdings, shares |  |  | (22) | 22 |  |
Net income (loss) | 79,390 |  |  |  |  | 79,390
Balance at Dec. 31, 2011 | 634,238 |  | 921 | (602) | 647,374 | (13,455)
Balance, shares at Dec. 31, 2011 |  |  | 92,461 | 22 |  |
Stock-based compensation | 10,573 |  |  |  | 10,573 |
Stock-based compensation, shares |  |  | 949 |  |  |
Vesting of restricted shares |  |  | 4 |  | (4) |
Treasury stock - tax withholdings | (3,194) |  |  | (3,194) |  |
Treasury stock - tax withholdings, shares |  |  | (107) | 107 |  |
Net income (loss) | 153,388 |  |  |  |  | 153,388
Balance at Dec. 31, 2012 | $ 795,005 |  | $ 925 | $ (3,796) | $ 657,943 | $ 139,933
Balance, shares at Dec. 31, 2012 |  |  | 93,303 | 129 |  |

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