Completion of Acquisition and Dispositon of Assets (Tables)

12 Months Ended

Dec. 31, 2014

Business Combination Tables [Abstract]

Pro Forma Financial Information Table Table [Text Block]

		For the year ended December 31,
		2014		2013
Revenues	$	1,421,537	$	1,160,394
Net income	$	531,188	$	164,303
Net income per common share - basic	$	3.47	$	1.07
Net income per common share - fully diluted	$	3.43	$	1.06

Adjusted Cash Payment Allocation Table Table [Text Block]

Adjusted cash payment			$890,785
Assets:
	Joint interest billing and other receivables - SWEPI Properties		(4,182)
	Other current assets:
		Acquired condensate inventory - SWEPI Properties	819
		Acquired yard inventory - SWEPI Properties	3,515
	Subtotal - Other current assets		4,334
	Proven oil and gas properties		1,033,960
	Property, plant and equipment:
		Divested gathering system - Pennsylvania Properties	(98,580)
		Acquired other fixed assets - SWEPI Properties	869
		Divested other fixed assets - Pennsylvania Properties	(50)
	Subtotal - Property, plant and equipment		(97,761)
Total assets acquired, net of divested assets			$936,351
Liabilities:
	Current liabilities:
		Current liabilities - Pennsylvania Properties	8,657
		Current liabilities - SWEPI Properties	(601)
	Subtotal - Current liabilities		$8,056
	Other long-term obligations:
		Acquired asset retirement obligations - SWEPI Properties	53,270
		Divested asset retirement obligations - Pennsylvania Properties	(15,760)
	Subtotal - Other long-term obligations		37,510
Total liabilities, net			$45,566