Credit Facility (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Credit Facility (Additional Textual) [Abstract]
Company revolving line of credit	$ 150,000
Amount available for borrowing	60,000
Date of balance outstanding on the credit facility	Oct. 24, 2016
Balance outstanding on the credit facility	47,450		47,450
Federal Funds rate	0.50%
Average interest rate on the facility	3.50%
Interest capitalized	45	72
Credit Facility (Textual) [Abstract]
Interest expense, net	332	280
Current ratio of the company	1.0
Ratio of EBITDAX	1.5
Funded debt to EBITDAX ratio	3.5
Interest expense, net
Credit Facility (Textual) [Abstract]
Interest expense, net	$ 409	$ 329
Minimum
Credit Facility (Textual) [Abstract]
Margin on the level of funds borrowed, rate	0.75%
Maximum
Credit Facility (Textual) [Abstract]
Margin on the level of funds borrowed, rate	2.75%