Variable Interest Entities (Details) (USD $)	Oct. 31, 2012	Oct. 31, 2011
Variable Interest Entity [Line Items]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets	$ 87,867,000	$ 85,121,000
Cardinal Pipeline Company [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets	17,969,000	18,323,000
Pine Needle Company [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets	19,239,000	18,690,000
South Star Energy Services [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets	18,118,000	17,536,000
Piedmont Hardy Storage [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets	$ 32,541,000	$ 30,572,000