Derivative Instruments (Offsetting Assets) (Details) (Accounts receivable monetized gains-affiliate, USD $)	Mar. 31, 2014	Dec. 31, 2013
Accounts receivable monetized gains-affiliate
Derivative [Line Items]
Affiliate Balances, Offsetting Derivative Assets, Gross Amounts of Recognized Assets	$ 97,100	$ 129,100
Affiliate Balances, Offsetting Derivative Assets, Gross Amounts Offset in the Balance Sheets	(45,100)	(45,900)
Affiliate Balances, Offsetting Derivative Assets, Net Amount of Assets Presented in the Balance Sheets	$ 52,000	$ 83,200