Variable Interest Entities (Details) (USD $)	Apr. 30, 2012	Oct. 31, 2011
Variable Interest Entity [Line Items]
Variable Interest Entity Nonconsolidated Carrying Amount Assets	$ 88,687,000	$ 85,121,000
Cardinal Pipeline Company [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity Nonconsolidated Carrying Amount Assets	22,101,000	18,323,000
Pine Needle Company [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity Nonconsolidated Carrying Amount Assets	18,680,000	18,690,000
South Star Energy Services [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity Nonconsolidated Carrying Amount Assets	16,017,000	17,536,000
Piedmont Hardy Storage [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity Nonconsolidated Carrying Amount Assets	$ 31,889,000	$ 30,572,000