Equity Transactions and Stock-Based Compensation Plans Schedule of Stock-Based Compensation Activity (Details) (USD $)	12 Months Ended
Dec. 31, 2012 Years	Dec. 31, 2011	Dec. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Outstanding, Number	1,130,844	1,531,237	2,184,683
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Outstanding, Weighted Average Grant Date Price	$ 4.89	$ 3.98	$ 3.83
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Grants in Period, Number	530,156	602,298
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Grants in Period, Weighted Average Grant Date Price	$ 5.02	$ 4.69
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Vested in Period, Number	(901,817)	(1,154,360)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Vested in Period, Weighted Average Grant Date Price	$ 3.42	$ 4.03
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Forfeitures in Period	28,732	101,384
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Forfeitures in Preiod, Weighted Average Grant Date Price	$ 4.74	$ 4.34
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	5,649,991	5,563,348	5,688,279
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 10.09	$ 10.20	$ 9.98
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	530,156	602,298
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	$ 8.72	$ 9.05
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period	(271,097)	(210,184)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price	$ 13.60	$ 12.41
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	(172,416)	(517,045)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price	$ 4.02	$ 5.58
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term	5.8
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number	4,519,147
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price	$ 10.41
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term	5.1

Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Forfeitures in Period

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(1)(c), d(2)

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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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- Definition

The weighted average period between the balance sheet date and expiration for all vested portions of options outstanding and currently exercisable (or convertible) under the plan, which may be expressed in a decimal value for number of years.

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- Definition

The weighted average price at which option holders acquired shares when converting their stock options into shares under the plan during the reporting period.

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-Name Statement of Financial Accounting Standard (FAS)

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- Definition

For presentations that combine terminations, 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 or that expired.

+ References

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- Definition

The combined weighted average exercise price associated with stock options during the period that have either lapsed or been forfeited.

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Gross number of share options (or share units) granted during the period.

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The weighted average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on stock options awarded under the plan during the reporting period.

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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.

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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.

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The weighted average period between the balance sheet date and expiration for all awards outstanding under the plan, which may be expressed in a decimal value for number of years.

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Number of share options (or share units) exercised during the current period.

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