SUPPLEMENTAL CASH FLOW DISCLOSURES (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
SUPPLEMENTAL CASH FLOW DISCLOSURES
Interest paid	$ 421,019	$ 247,879	$ 37,719
Income taxes paid	$ 41,425	$ 45,399	$ 26,300