Stock Based Compensation (Details) (USD $)	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Number of Stock Options
Outstanding at beginning of year, Number of Stock Options	28,129,885	24,262,692
Granted, Number of Stock Options	1,567,119	4,195,000
Exercised, Number of Stock Options	(6,412)	(126,387)
Forfeited, Number of Stock Options	(7,500)	(47,500)
Outstanding at end of year, Number of Stock Options	29,683,092	28,283,805
Weighted Average Exercise Price
Outstanding at beginning of year, Weighted Average Exercise Price	$ 12.68	$ 12.51
Granted, Weighted Average Exercise Price	$ 9.53	$ 13.13
Exercised, Weighted Average Exercise Price	$ 5.96	$ 6.53
Forfeited, Weighted Average Exercise Price	$ 12.76	$ 14.79
Outstanding at end of year, Weighted Average Exercise Price	$ 12.51	$ 12.63

Number of Stock Options.

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Share Based Compensation Arrangement By Share Based Payment Award Option Exercises In Period Weighted Average Exercise Price.

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Share Based Compensation Arrangement By Share Based Payment Award Option Forfeitures In Period Weighted Average Exercise Price.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Option Grants In Period Weighted Average Exercise Price.

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Weighted Average Exercise Price.

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- Definition

The decrease in the number of reserved shares that could potentially be issued attributable to the exercise or conversion during the reporting period of previously issued stock options under the option plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(1)(e)

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(1)(f)

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- Definition

The quantity of shares issuable on stock options awarded under the plan during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(1)(d)

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- Definition

The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance-sheet date, including vested options.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(1)(a)

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(1)(b)

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- Definition

The weighted average price as of the beginning of the year at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(1)(a)

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