Fair Value Of Assets And Liabilities (Narrative) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014 contract	Dec. 31, 2013 contract
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of futures contracts (as shown)	6	2
Future [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notional value of futures contracts	0.8	0.3
Note Payable [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Note payable		0.3