Property, Plant and Equipment (Tables)

6 Months Ended

Jun. 30, 2014

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment

	June 30, 2014		December 31, 2013
Coal and other plant and equipment	$	3,711,184	$	3,681,051
Intangible drilling cost	2,228,806		1,937,336
Proven gas properties	1,683,052		1,670,404
Unproven gas properties	1,493,708		1,463,406
Coal properties and surface lands	1,407,518		1,409,408
Gas gathering equipment	1,074,265		1,058,008
Gas wells and related equipment	780,212		688,548
Airshafts	443,657		397,466
Mine development	416,296		354,607
Leased coal lands	388,033		388,020
Coal advance mining royalties	387,199		381,348
Other gas assets	124,903		126,239
Gas advance royalties	22,134		22,668
Total Property Plant and Equipment	14,160,967		13,578,509
Less: Accumulated DD&A	4,384,209		4,136,247
Total Net PP&E	$	9,776,758	$	9,442,262