Other Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2017

Other Intangible Assets Disclosure [Abstract]

Schedule of Intangible Assets

Our identifiable intangible assets are as follows (in thousands):

	Useful			Accumulated
As of December 31, 2017	Life	Gross		Amortization			Net
Intangible assets subject to amortization:
Supply contract	11.5	$	12,227	$	(12,138	)	$	89
Intangible assets not subject to amortization:
Rights-of-way assets	Indefinite	15,828					15,828
Total		$	28,055	$	(12,138	)	$	15,917

	Useful			Accumulated
As of December 31, 2016	Life	Gross		Amortization			Net
Intangible assets subject to amortization:
Supply contract	11.5	$	12,227	$	(11,075	)	$	1,152
Intangible assets not subject to amortization:
Rights-of-way assets	Indefinite	13,268					13,268
Total		$	25,495	$	(11,075	)	$	14,420