Capitalized Costs and Accumulated Depreciation, Depletion and Amortization (Tables)

3 Months Ended

Mar. 31, 2015

Extractive Industries [Abstract]

Capitalized Costs and Accumulated Depreciation, Depletion and Amortization

	March 31, 2015			December 31, 2014
	(in thousands)
Natural gas and oil properties:
Properties subject to depletion	$	9,745,129		$	9,624,725
Unproved properties		942,606			943,246
Total		10,687,735			10,567,971
Accumulated depreciation, depletion and amortization		(2,581,753	)		(2,590,398	)
Net capitalized costs	$	8,105,982		$	7,977,573

— Includes capitalized asset retirement costs and the associated accumulated amortization.