Subsequent Events (Details Textual) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended			12 Months Ended			12 Months Ended				3 Months Ended
	Dec. 31, 2012 sqft	Mar. 14, 2013	Sep. 30, 2012	Dec. 31, 2012 Subsequent Event [Member]	Mar. 14, 2013 Subsequent Event [Member]	Mar. 11, 2013 Subsequent Event [Member]	Dec. 31, 2012 Maximum [Member] sqft	Dec. 31, 2012 Maximum [Member] Subsequent Event [Member]	Dec. 31, 2012 Minimum [Member] sqft	Dec. 31, 2012 Minimum [Member] Subsequent Event [Member]	Mar. 31, 2012 Open costless collar contracts [Member]
Derivative [Line Items]
Extension of drilling rig contracts											6 months
Increase of square footage							36,525		28,743
Borrowing base						$ 255.0
Borrowings outstanding under the Credit Agreement					180.0
Outstanding letters of credit	1.1			1.3	1.3
Additional deferred loan cost	0.1		0.8		0.3
Unamortized portion of the deferred loan costs				1.6
Stock option awards granted				507,500
Stock option awards granted, two				284,292
Weighted average exercise price, Options granted	$ 10.79			$ 8.21
Exercise prices common stock				$ 8.18
Fair value of awards				2.8
Restricted stock grants				324,771
Fair value of restricted stock awards				2.4
Vesting period of shares	4 years						4 years	4 years	3 years	3 years
Minimum outstanding aggregate commitments				5.6
Options to purchase Company's common stock, expired unexercised or were forfeited	248,000			408,000
Options expired unexercised or were forfeited, share price	$ 10.00			$ 10.00
Subsequent Events (Textual) [Abstract]
Maximum outstanding aggregate termination obligations of contracts		$ 2.1
Increase In Square Footage	7,782