Acquisition Acquisition (Details Textuals) (USD $)	12 Months Ended
	Dec. 31, 2012 facilities
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Number of Businesses Acquired	14
Business Acquisition, Cost of Acquired Entity, Cash Paid	$ 220,000,000
Business Acquisition, Purchase Price Allocation, Liabilities Assumed	74,000,000
Business Acquisition, Cost of Acquired Entity, Purchase Price	294,000,000
Number of Acquired Business's are VIEs - Parent is not Primary Beneficiary	2
Exposure Loss Related to the Debt Assumed	0
Business Acquisition, Purchase Price Allocation, Amortizable Intangible Assets	75,000,000
Amortization Years for Intangible Assets Acquired in a Business Combination	8 years
Revenues of Acquired Business Included in the Company's Consolidated Statement of Operations	30,000,000
Earnings of Acquired Business Included in the Company's Consolidated Statements of Operations	$ 2,000,000
The Period of the Acquired Project Companies Following the Colsing	3 months
Maximum [Member]
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Equity Method Investment, Ownership Percentage	100.00%
Minimum [Member]
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Equity Method Investment, Ownership Percentage	46.00%