Basis of preparation and consolidation Basis of preparation and consolidation (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013
Reclassification From Financing To Operating Cash Flows [Member]
Reclassification Adjustment	$ 19,400
Reclassification From Finance Expenses Into Income Attributable To Operating Affiliate Investors [Member]
Reclassification Adjustment	$ (10,077)