Equity Method Investment (Details) (USD $)	3 Months Ended			6 Months Ended					6 Months Ended		3 Months Ended
	Jun. 30, 2012		Jun. 30, 2011	Jun. 30, 2012		Jun. 30, 2011	Dec. 31, 2011		Jun. 30, 2012 CCGGC [Member]	Jun. 30, 2011 CCGGC [Member]	Mar. 31, 2011 Sullivan Energy Ventures LLC [Member]	Dec. 31, 2010 Sullivan Energy Ventures LLC [Member]	Jun. 30, 2011 Sullivan Energy Ventures LLC [Member]
Equity Method Investment (Textual)
Ownership interest in equity method investment (as a percent)									50.00%
Equity investment income	$ 26,000		$ 56,000	$ 27,000		$ 41,000			$ 27,000	$ 41,000
Ownership interest acquired in affiliates (as a percent)												17.50%
Investments in affiliates	1,241,000	[1]		1,241,000	[1]		1,126,000	[1]					463,000
Oil and gas reserves												796,000
Oil and gas reserves (in Mcf)												663,000
Additional oil and gas asset impairment expense, had affiliate reserves and related property balance had not been included in the ceiling test calculation											$ 280,000

[1] (note 6)