Provision (Benefit) for Income Taxes (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Provision (Benefit) for Income Taxes
Income tax benefit included in current taxes	$ 1,144,000	$ (1,616,000)	$ 2,957,000
Non-deductible equity compensation	1,911,000	1,537,000	867,000
Provision for state income taxes	100,000	1,500,000	600,000
Income Tax Expense (Benefit)	(15,639,000)	(50,494,000)	(27,833,000)
Income tax reconciliation state income tax deferred liabilities	900,000	2,700,000
Valuation allowance of carryover tax assets	(2,100,000)	(2,300,000)
Liability for uncertain tax positions	(977,000)	0	0
Increase in deferred tax assets	37,500,000
Deferred tax assets increase in operating loss net of excess stock based compensation	38,400,000
Decrease in deferred tax assets other	1,400,000
Increase in deferred tax liabilities	55,100,000
Increase in deferred tax liabilities attributable to oil and gas exploration and development costs	53,900,000
Federal NOL tax assets	93,600,000	54,954,000	30,700,000
NOLs for excess stock-based compensation	(9,676,000)	(9,450,000)	7,600,000
Operating loss carryforwards	13,686,000	11,377,000
State valuation allowance	6,000,000
Unrealized stock compensation	9,096,000	7,151,000
Change in valuation allowance	2,400,000
Internal Revenue Service (IRS) [Member]
Provision (Benefit) for Income Taxes
Income tax benefit included in current taxes	1,400,000
State and Local Jurisdiction [Member]
Provision (Benefit) for Income Taxes
Income tax benefit included in current taxes	(300,000)
State Income Tax Expense Prior to Louisiana Percentage Depletion Benefit	1,300,000
Income tax reconciliation state income tax deferred liabilities	(400,000)
Louisiana Net Operating Loss [Member]
Provision (Benefit) for Income Taxes
Change in valuation allowance	2,100,000
Charitable Contribution Carryforwards [Member]
Provision (Benefit) for Income Taxes
Change in valuation allowance	300,000
Louisiana Percentage Depletion Benefit [Member] | State and Local Jurisdiction [Member]
Provision (Benefit) for Income Taxes
Income Tax Expense (Benefit)	1,400,000
Income tax reconciliation state income tax deferred liabilities	$ (1,300,000)