(4) Investment in Savoy (Details) - Condensed Balance Sheet (Equity Investment in Savoy, USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2013
Equity Investment in Savoy
(4) Investment in Savoy (Details) - Condensed Balance Sheet [Line Items]
Current assets	$ 20,651
Oil and gas properties, net	23,018
	43,669
Total liabilities	12,422
Partners' capital	31,247
	$ 43,669