CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Allowance for doubtful accounts	$ 30	$ 30
Accumulated amortization, intangible assets	4,178	3,479
Property, Plant and Equipment, Gross	$ 369,047	$ 320,442
Common Stock, Par or Stated Value Per Share	$ 0.001	$ 0.001
Common Stock, Shares Authorized	25,000,000	25,000,000
Common Stock, Shares, Issued	10,429,091	10,296,891
Common Stock, Shares, Outstanding	10,429,091	10,296,891
Variable Interest Entity, Primary Beneficiary [Member]
Property, Plant and Equipment, Gross	$ 17,415	$ 16,237