Income Taxes - Reconciliation of current year change in valuation allowance (Details 4) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Valuation Allowance [Line Items]
Increase in valuation allowance for current year increase in net operating losses:	$ (2,000)
Decrease in valuation allowance for 382 limitations on tax attributes:	(26,924,000)
Increase in valuation allowance for current year net decrease in deferred tax assets other than net operating losses:	(10,288,000)
Increase in valuation allowance as a result of foreign currency fluctuation	246,000
Increase in valuation allowance due to current year change of deferred tax assets as the result of uncertain tax positions.	503,000
Valuation allowance (decrease) increase	(36,465,000)
United States
Valuation Allowance [Line Items]
Increase in valuation allowance for current year increase in net operating losses:
Decrease in valuation allowance for 382 limitations on tax attributes:	(26,924,000)
Increase in valuation allowance for current year net decrease in deferred tax assets other than net operating losses:	(10,661,000)
Increase in valuation allowance as a result of foreign currency fluctuation
Increase in valuation allowance due to current year change of deferred tax assets as the result of uncertain tax positions.
Valuation allowance (decrease) increase	(37,585,000)	(205,371,000)	14,820,000
Foreign
Valuation Allowance [Line Items]
Increase in valuation allowance for current year increase in net operating losses:	(2,000)
Decrease in valuation allowance for 382 limitations on tax attributes:
Increase in valuation allowance for current year net decrease in deferred tax assets other than net operating losses:	373,000
Increase in valuation allowance as a result of foreign currency fluctuation	246,000
Increase in valuation allowance due to current year change of deferred tax assets as the result of uncertain tax positions.	503,000
Valuation allowance (decrease) increase	$ 1,120,000	$ 772,000	$ 1,904,000