Product Sales Revenue (Disclosure Of Product Sales Revenue) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Product Sales Revenue [Abstract]
Physical sale of petroleum products	$ 561,410	$ 733,654	$ 755,266
NYMEX Adjustments Included in Product Sales	68,426	145,320	(10,597)
Total product sales revenues	$ 629,836	$ 878,974	$ 744,669