Significant Accounting Policies (Other Policies) (Details Textuals) (USD $)	Dec. 31, 2012	Dec. 31, 2011
Asset Retirement Obligation [Abstract]
Asset Retirement Obligation, Current	$ 500,000
Gas Imbalance Asset Liability [Abstract]
Gas Balancing Payable, Current	2,300,000	2,300,000
Gas Balancing Asset (Liability)	1,533,000	1,658,000
Other Assets, Noncurrent [Abstract]
Deferred Finance Costs, Noncurrent, Net	$ 25,989,000	$ 24,212,000