Property, Plant and Equipment

12 Months Ended

Dec. 31, 2017

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment

PROPERTY, PLANT AND EQUIPMENT:

Property, plant and equipment consists of the following at December 31:

	December 31,
	2017		2016
Plant and Equipment	$	2,757,062	$	2,680,453
Coal Properties and Surface Lands	857,031		861,048
Airshafts	392,266		381,755
Mine Development	344,139		344,139
Advance Mining Royalties	325,855		326,000
Total Property, Plant and Equipment	4,676,353		4,593,395
Less Accumulated Depreciation, Depletion and Amortization	2,554,056		2,413,125
Total Property, Plant and Equipment, Net	$	2,122,297	$	2,180,270

Coal reserves are controlled either through fee ownership or by lease. The duration of the leases vary; however, the lease terms are generally extended automatically to the exhaustion of economically recoverable reserves, as long as active mining continues. Coal interests held by lease provide the same rights as fee ownership for mineral extraction and are legally considered real property interests.

As of December 31, 2017 and 2016, property, plant and equipment includes gross assets under capital lease of $3,559 and $3,547, respectively. Accumulated amortization for capital leases was $2,839 and $2,399 at December 31, 2017 and 2016, respectively. Amortization expense for assets under capital leases approximated $424 and $491 for the years ended December 31, 2017 and 2016, respectively, and is included in Depreciation, Depletion and Amortization in the accompanying Consolidated Statements of Income. See Note 12–Leases for further discussion of capital leases.