Derivative Instruments (Gross Fair Values of Receivable and Payable Affiliate Balances) (Details) (USD $)	Dec. 31, 2012	Dec. 31, 2011
Derivative [Line Items]
Affiliate Balances, Offsetting Derivative Assets, Gross Amounts Of Recognized Assets	$ 82,800	$ 210,700
Affiliate Balances, Offsetting Derivative Assets, Gross Amounts Offset In The Balance Sheets	(19,400)
Affiliate Balances, Offsetting Derivative Assets, Net Amount Of Assets Presented In The Balance Sheets	63,400	210,700
Affiliate Balances, Offsetting Derivative Liabilities, Gross Amounts Of Recognized Liabilities	(22,500)
Affiliate Balances, Offsetting Derivative Liabilities, Gross Amounts Offset In The Balance Sheets	19,400
Affiliate Balances, Offsetting Derivative Liabilities, Net Amount Of Liabilities Presented In The Balance Sheets	(3,100)
Accounts Receivable Monetized Gains Affiliate [Member]
Derivative [Line Items]
Affiliate Balances, Offsetting Derivative Assets, Gross Amounts Of Recognized Assets	69,000	127,400
Affiliate Balances, Offsetting Derivative Assets, Gross Amounts Offset In The Balance Sheets	(5,600)
Affiliate Balances, Offsetting Derivative Assets, Net Amount Of Assets Presented In The Balance Sheets	63,400	127,400
Long Term Accounts Receivable Monetized [Member]
Derivative [Line Items]
Affiliate Balances, Offsetting Derivative Assets, Gross Amounts Of Recognized Assets	13,800	83,300
Affiliate Balances, Offsetting Derivative Assets, Gross Amounts Offset In The Balance Sheets	(13,800)
Affiliate Balances, Offsetting Derivative Assets, Net Amount Of Assets Presented In The Balance Sheets		83,300
Put Premiums Payable Affiliate [Member]
Derivative [Line Items]
Affiliate Balances, Offsetting Derivative Liabilities, Gross Amounts Of Recognized Liabilities	(5,600)
Affiliate Balances, Offsetting Derivative Liabilities, Gross Amounts Offset In The Balance Sheets	5,600
Affiliate Balances, Offsetting Derivative Liabilities, Net Amount Of Liabilities Presented In The Balance Sheets
Long Term Put Premiums Payable Affiliate [Member]
Derivative [Line Items]
Affiliate Balances, Offsetting Derivative Liabilities, Gross Amounts Of Recognized Liabilities	(16,900)
Affiliate Balances, Offsetting Derivative Liabilities, Gross Amounts Offset In The Balance Sheets	13,800
Affiliate Balances, Offsetting Derivative Liabilities, Net Amount Of Liabilities Presented In The Balance Sheets	$ (3,100)