v2.4.0.6

Earnings Per Share (Tables) | 12 Months Ended
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Dec. 31, 2011
Earnings Per Share [Abstract] |
Schedule Of Net Income Attributable To Common Stockholders |
|  | Year Ended December 31, |
|  | 2011 |  |  | 2010 |  |  | 2009 |
Net income |  | $ | 258,966 |  |  | $ | 221,393 |  |  | $ | 52,995 |
Less: |  |  |  |  |  |  |  |  |  |  |  |
Net income attributable to participating securities |  |  | (2,310 | ) |  |  | (2,230 | ) |  |  | (475 | )
Net income attributable to common shareholders |  | $ | 256,656 |  |  | $ | 219,163 |  |  | $ | 52,520 |
Reconciliation Of Denominator For Basic And Diluted Earnings (Loss) Per Share |
|  | Year Ended December 31, |
|  | 2011 |  |  | 2010 |  |  | 2009 |
Weighted average common shares—basic |  |  | 65,927,421 |  |  |  | 65,472,875 |  |  |  | 65,323,101 |
Plus incremental shares from: |  |  |  |  |  |  |  |  |  |  |  |
Assumed exercise of options |  |  | 372,737 |  |  |  | 203,789 |  |  |  | 98,289 |
Weighted average common shares—diluted |  |  | 66,300,158 |  |  |  | 65,676,664 |  |  |  | 65,421,390 |
Earnings per share: |  |  |  |  |  |  |  |  |  |  |  |
Basic |  | $ | 3.89 |  |  | $ | 3.35 |  |  | $ | 0.80 |
Diluted |  | $ | 3.87 |  |  | $ | 3.34 |  |  | $ | 0.80 |

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- Definition Tabular disclosure of the weighted average number of shares used in calculating basic net earnings per share (or unit) and diluted earnings per share (or unit). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Topic 260 -SubTopic 10 -Publisher FASB -Number -Article -Subparagraph -Name Accounting Standards Codification -Paragraph 1 -Section 50 -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details
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- Definition Schedule of net income (loss) attributable to common stockholders [Table Text Block] + References No definition available. + Details
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