Long-Term Debt (Tables)

12 Months Ended

Dec. 31, 2017

Long-Term Debt

Schedule of interest incurred and paid on the credit facility, interest capitalized related to facilities and equipment under construction, and the related weighted average interest rates on long term debt

Years Ended December 31,	2017			2016			2015
(in thousands except interest rate data)
Interest incurred	$	415		$	449		$	1,913
Capitalized interest	$	—		$	—		$	534
Interest paid (net of capitalized interest)	$	181		$	284		$	1,169
Weighted average interest rate		—	%		—	%		2.2	%