Earnings Per Share (Details) (USD $) In Thousands, except Share data	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Earnings Per Share
Net income - basic earnings per share	$ 22,362	$ 17,922	$ 39,537	$ 33,902
Interest expense on convertible debt	5	5	10	10
Net income after assumed conversion - diluted earnings per share	$ 22,367	$ 17,927	$ 39,547	$ 33,912
Basic weighted average common shares outstanding	123,254,895	113,878,018	121,732,522	113,814,527
Net effect of dilutive stock options, warrants, restricted stock and convertible debt	839,894	437,156	800,164	374,751
Diluted weighted average common shares outstanding	124,094,789	114,315,174	122,532,686	114,189,278
Basic earnings per share	$ 0.18	$ 0.16	$ 0.32	$ 0.30
Diluted earnings per share	$ 0.18	$ 0.16	$ 0.32	$ 0.30
Common stock excluded from computation of diluted earnings per share	336,573	720,194	356,393	889,474

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) in the future that were not included in the computation of diluted EPS because to do so would increase EPS amounts or decrease loss per share amounts for the period presented.

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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 128
-Paragraph 13, 14

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The amount of net income or loss for the period per each share of common stock outstanding during the reporting period.

+ References

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The amount of net income or loss for the period per each share of common stock and dilutive common stock equivalents outstanding during the reporting period.

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In computing the dilutive effect of convertible debt, the earnings per share numerator is adjusted to add back the after-tax amount of interest recognized in the period associated with any convertible debt.

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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Net Income (Loss) Available to Common Stockholders plus adjustments resulting from the assumption that dilutive convertible securities were converted, options or warrants were exercised, or that other shares were issued upon the satisfaction of certain conditions.

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The average number of shares issued and outstanding that are used in calculating diluted EPS, determined based on the timing of issuance of shares in the period.

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