Organization and Business (Details 2) - Equal to or less than t in Millions	Jun. 30, 2015 t
Westshore | 2015 Exports
Organization and Business
Committed Capacity	4.3
Westshore | Committed Capacity As Of Q2 2015 [Member]
Organization and Business
Committed Capacity Adjustment	1.0
Westshore | Committed Capacity Second Half 2015 Member [Member]
Organization and Business
Committed Capacity Adjustment	0.9
Millennium
Organization and Business
Throughput Option	7.7
SSA Marine
Organization and Business
Throughput Option	17.6