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Net Income Per Share (Options and Warrants Excluded From the Calculation) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009
Options excluded from diluted earnings per share | 3.1 | 2.5 | 1.9
Warrants excluded from diluted earnings per share | 6.3 | 2.1 |
Exercise price of excluded warrants | $ 7.50 | $ 7.50 |
Maximum [Member] |  |  |
Exercise price of excluded options | $ 14.28 | $ 14.28 | 16.90
Minimum [Member] |  |  |
Exercise price of excluded options | $ 3.72 | $ 5.18 | 5.00

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- Definition The exercise price of each class of warrants or rights outstanding. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 4 -Section 08 -Paragraph i -Subparagraph 4 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(i)(4)) -URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690 + Details
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