Supplemental Cash Flow Information - Operating assets and liabilities (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Components of operating assets and liabilities
Decrease (increase) in restricted cash	$ 6,766	$ (2,193)
Decrease (increase) in accounts receivable	(2,248)	(13,741)
Decrease (increase) in receivable from affiliates	(1,353)	37,472
Decrease (increase) in inventories	(36,065)	(6,037)
Decrease (increase) in derivatives and margin deposits	(287)	(240)
Decrease (increase) in other current assets	(3,134)	(2,631)
Decrease (increase) in other assets	(2,096)	4
Increase (decrease) in accounts payable and accrued liabilities	18,730	(14,224)
Increase (decrease) in payable to affiliates	5,580	(39,567)
Increase (decrease) in payables to pre-petition creditors	(3,836)	(46)
Increase (decrease) in other noncurrent liabilities	47	1,284
Total changes in operating assets and liabilities	$ (17,896)	$ (39,919)