Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2012

Summary of Significant Accounting Policies [Abstract]

Change in asset retirement obligation account activity

	2012		2011
Balance, beginning	$	148,515	$	141,407
Accretion of liability due to passage of time		5,452		4,940
Amortization of asset due to passage of time		—		2,168
Balance, ending	$	153,967	$	148,515