Asset Retirement Obligation (Tables)

6 Months Ended

Jun. 30, 2012

Asset Retirement Obligation [Abstract]

Schedule of Asset Retirement Obligation [Table Text Block]

	Three Months Ended		Six Months Ended
	June 30,		June 30,
	2012	2011	2012	2011
Asset retirement obligation at beginning of period	$   4,878,100	$   4,511,600	$                         4,836,500	$                         4,444,900
Liabilities settled	(800)	—	(20,800)	—
Accretion expense	61,600	66,600	123,200	133,300
Asset retirement obligation at end of period	$   4,938,900	$   4,578,200	$                         4,938,900	$                         4,578,200