Acquisitions And Disposal - Schedule of Gain on Disposal of Properties (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Business Combinations [Abstract]
Total consideration received	$ 6,525
Carrying value of Churchrock project	(2,123)
Carrying value of other plant and equipment	(31)
Accounts payable	1
Asset retirement obligation	105
Royalty payable on Churchrock project	450
Gain on disposal of HRI	$ 4,927

The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration