11. Fair Value measurements (Details 5) (USD $) In Thousands, except Per Share data, unless otherwise specified	9 Months Ended	12 Months Ended
Sep. 30, 2012	Dec. 31, 2011
DerivativeFinancialInstrumentsLiabilitiesMember
Qualitative information about level 3 fair value measurements
Fair Values	$ 95	$ 967
Valuation Techniques	Binomial	Binomial
Stock price	$ 3	$ 0.89
Volatility	40.00%	38.90%
Risk free rate	1.30%
DerivativeFinancialInstrumentsLiabilitiesMember \| MinimumMember
Qualitative information about level 3 fair value measurements
Risk free rate		1.30%
DerivativeFinancialInstrumentsLiabilitiesMember \| MaximumMember
Qualitative information about level 3 fair value measurements
Risk free rate		1.70%
DebtSecuredReceivablesMember
Qualitative information about level 3 fair value measurements
Fair Values	$ 76,630	$ 166,828
Valuation Techniques	Discounted cash flows	Discounted cash flows
Discount rate	16.20%	16.20%

Measure of dispersion, in percentage terms (for instance, the standard deviation or variance), for a given stock price.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

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Risk that one party to the contract will default expressed as a percentage, used as an input to measure fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Price at which a dealer is willing to buy an instrument, used as an input to measure fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Description of the valuation processes in place for fair value measurements categorized within Level 3 of the fair value hierarchy.

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This element represents the aggregate of the liabilities reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

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