Common Equity Common Equity 4 (Details) (USD $)	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2011
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	11,925,226	11,925,226
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 21.40	$ 21.40
Non Vested Options [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	3,210,680	5,272,570
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period	0	458,180
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period	57,170	2,577,240
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	3,153,510	3,153,510
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 3.78	$ 4.27
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 0	$ 3.17
Share Based Compensation Arrangements By Share Based Payment Awards Options Vested In Period Weighted Average Fair Value	$ 3.78	$ 4.66
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Intrinsic Value	$ 0	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 3.78	$ 3.78
Employee Service Share-based Compensation, Unrecognized Compensation Costs on Nonvested Awards, Weighted Average Period of Recognition		14
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized	$ 1,900,000	$ 1,900,000

As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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The weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, using a decimal to express in number of years.

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The combined weighted average of the accumulated differences between the fair values on underlying shares and exercises prices to acquire such shares as of the grant date on options that were either forfeited or lapsed.

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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.

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

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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