Variable Interest Entities (Details) (Variable Interest Entity, Not Primary Beneficiary [Member], USD $)	Apr. 30, 2013	Oct. 31, 2012
Variable Interest Entity [Line Items]
Variable Interest Entity Nonconsolidated Carrying Amount Assets	$ 94,766,000	$ 87,867,000
Cardinal Pipeline Company [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity Nonconsolidated Carrying Amount Assets	18,270,000	17,969,000
Pine Needle Company [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity Nonconsolidated Carrying Amount Assets	18,585,000	19,239,000
South Star Energy Services [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity Nonconsolidated Carrying Amount Assets	15,467,000	18,118,000
Piedmont Hardy Storage [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity Nonconsolidated Carrying Amount Assets	33,465,000	32,541,000
Constitution Pipeline Company [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity Nonconsolidated Carrying Amount Assets	$ 8,979,000	$ 0