Summary of Significant Accounting Policies (Details) (USD $)	3 Months Ended		9 Months Ended		12 Months Ended											9 Months Ended		9 Months Ended								3 Months Ended		9 Months Ended		12 Months Ended	3 Months Ended			9 Months Ended								9 Months Ended
	Sep. 30, 2012 mi	Sep. 30, 2011	Sep. 30, 2012 mi	Sep. 30, 2011	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Sep. 30, 2012 Commodity Contract [Member] Not Designated as Hedging Instrument [Member] Current Assets [Member]	Dec. 31, 2011 Commodity Contract [Member] Not Designated as Hedging Instrument [Member] Current Assets [Member]	Sep. 30, 2012 Commodity Contract [Member] Not Designated as Hedging Instrument [Member] Other Assets [Member]	Dec. 31, 2011 Commodity Contract [Member] Not Designated as Hedging Instrument [Member] Other Assets [Member]	Sep. 30, 2012 Commodity Contract [Member] Not Designated as Hedging Instrument [Member] Current Liabilities [Member]	Dec. 31, 2011 Commodity Contract [Member] Not Designated as Hedging Instrument [Member] Current Liabilities [Member]	Sep. 30, 2012 Commodity Contract [Member] Not Designated as Hedging Instrument [Member] Other Liabilities [Member]	Dec. 31, 2011 Commodity Contract [Member] Not Designated as Hedging Instrument [Member] Other Liabilities [Member]	Sep. 30, 2012 Wells Fargo Bank [Member]	Dec. 31, 2011 Wells Fargo Bank [Member]	Sep. 30, 2012 Revenue [Member]	Sep. 30, 2012 Revenue [Member] Customer Concentration Risk [Member]	Sep. 30, 2012 Accounts Receivable [Member]	Sep. 30, 2012 Accounts Receivable [Member] Product Concentration Risk [Member]	Sep. 30, 2012 Minimum [Member]	Sep. 30, 2012 Minimum [Member] Customer Concentration Risk [Member]	Sep. 30, 2012 Maximum [Member]	Sep. 30, 2012 Maximum [Member] Customer Concentration Risk [Member]	Sep. 30, 2012 Producing Oil and Gas Properties [Member]	Sep. 30, 2011 Producing Oil and Gas Properties [Member]	Sep. 30, 2012 Producing Oil and Gas Properties [Member]	Sep. 30, 2011 Producing Oil and Gas Properties [Member]	Dec. 31, 2011 Producing Oil and Gas Properties [Member]	Sep. 30, 2012 Non-Producing Oil and Gas Properties [Member]	Sep. 30, 2011 Non-Producing Oil and Gas Properties [Member]	Mar. 31, 2011 Non-Producing Oil and Gas Properties [Member]	Sep. 30, 2012 Non-Producing Oil and Gas Properties [Member]	Sep. 30, 2011 Non-Producing Oil and Gas Properties [Member]	Sep. 30, 2012 South Texas Project acreage [Member]	Dec. 31, 2011 South Texas Project acreage [Member]	Sep. 30, 2012 West Texas Project acreage [Member]	Dec. 31, 2011 West Texas Project acreage [Member]	Sep. 30, 2012 Napoleonville, Louisiana acreage [Member]	Dec. 31, 2011 Napoleonville, Louisiana acreage [Member]	Sep. 30, 2012 Other acreage areas [Member]	Dec. 31, 2011 Other acreage areas [Member]
Nature of Operations and Principles of Consolidation [Abstract]
Primary area of operation (in miles)	1,000		1,000
Cash and Cash Equivalents [Abstract]
Maximum maturity period			90 days
Components of prepayments [Abstract]
Cash collateral deposits for commodity purchases	$ 5,000,000		$ 5,000,000		$ 6,521,000
Insurance premiums	2,033,000		2,033,000		2,033,000
Commodity imbalances and futures	1,061,000		1,061,000		1,452,000
Rents, license and other	1,077,000		1,077,000		645,000
Prepayments, total	9,171,000		9,171,000		10,651,000
Property, Plant and Equipment [Line Items]
Property and equipment, useful life																						3 years		20 years
Impairment provisions			878,000	1,208,000																						19,000	252,000	90,000	252,000		230,000	395,000		788,000	956,000
Capitalized costs for non producing oil and gas leasehold interests specified as percentage of total costs (in hundredths)																															4.00%			4.00%
Total Non-producing Leasehold Costs	3,870,000		3,870,000		3,295,000																															3,073,000	2,212,000	206,000	288,000	323,000	320,000	268,000	475,000
Capitalized Costs, Oil and Gas Producing Activities, Net [Abstract]
Balance December 31, 2011			171,803,000																																							475,000
Property additions																																										675,000
Property sale																																										(94,000)
Impairments																																										(788,000)
Balance September 30, 2012	199,196,000		199,196,000		171,803,000																																					268,000
Proceeds from Sale of Oil and Gas Property and Equipment																														6,200,000			329,000	578,000
Gain on Sale of Oil and Gas Property	1,070,000	632,000	2,399,000	1,024,000																										2,708,000			125,000	475,000
Cash Deposits and Other Assets [Abstract]
Insurance collateral deposits	3,086,000		3,086,000		3,331,000
State collateral deposits	145,000		145,000		168,000
Materials and supplies	618,000		618,000		668,000
Cash deposits and other	3,849,000		3,849,000		4,167,000
Concentration of Credit Risk [Line Items]
Concentration risk, percentage (in hundredths)																			50.00%		90.00%
Concentration risk, additional characteristic																			Large crude oil refining concerns		Crude oil and natural gas marketing activities
Number of customers																							2		3
Percentage of US demand supplied by company			Less than one percent
Percentage of revenues from one customer which loss would not have material effect (in hundredths)																		10.00%
Industry practice payment of receivables																				25 days
Letter of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity																60,000,000
Standby letters of credit issued																53,800,000	38,900,000
Covenant terms																Such restrictions included the maintenance of a combined 1.1 to 1.0 current ratio and the maintenance of positive net earnings excluding inventory valuation changes, as defined, among other restrictions. The Company is currently in compliance with all such financial covenants.
Statement of Cash Flows [Abstract]
Interest paid			4,000	7,000
Income taxes paid			6,636,000	508,000
Proceeds from income tax refunds			2,095,000
Capital expenditures incurred but not yet paid			2,962,000	3,207,000	4,070,000	2,868,000
Earnings Per Share [Abstract]
Weighted average number of shares outstanding (in shares)					4,217,596	4,217,596	4,217,596
Contracts at gross valuation [Abstract]
Asset Derivatives								4,267,000	3,500,000	0	0	0	0	0	0
Liability Derivatives								0	0	0	0	(5,439,000)	2,117,000	0	0
Less Counterparty Offsets								(2,727,000)	(1,436,000)	0	0	2,727,000	(1,436,000)	0	0
As Reported Fair Value Contracts								$ 1,540,000	$ 2,064,000	$ 0	$ 0	$ (2,712,000)	$ 681,000	$ 0	$ 0