Supplemental Cash Flow Information (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Supplemental Cash Flow Information
Cash paid for interest, net of amounts capitalized	$ 109,001	$ 112,780	$ 101,459
Cash paid for income taxes, net of refunds	17,940	10,115	8,683
Supplemental schedule of non-cash investing and financing activities:
Accrued property, plant and equipment	408,557	87,098	65,908
Interest capitalized on construction in progress	26,061	1,121	2,766
Issuance of common units for vesting of share-based payment awards	2,510	5,412	7,238
Issuance of Class B units for acquisition of non-controlling interest		$ 752,531