Acquisitions (Details 3) - Carbon California [Member] $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($)
Fair value of Carbon common shares transferred as consideration	$ 8,327
Fair value of non-controlling interest	16,466
Fair value of previously held interest	7,243
Fair value of contribution associated with acquisition of Yorktown's interest in Carbon California	8,637
Fair value of business acquired	$ 40,673

Business combination fair value of contribution associated with acquisition.

No definition available.

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- Definition

This element represents the fair value of the noncontrolling interest in the acquiree at the acquisition date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=116869197&loc=d3e4845-128472

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6613-128477

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-Name Accounting Standards Codification
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-SubTopic 30
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-Paragraph 1
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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
-Section 30
-Paragraph 7
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- Definition

Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=116868840&loc=d3e2207-128464

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- Definition

Fair value at acquisition-date of the equity interest in the acquiree held by the acquirer, immediately before the acquisition date for businesses combined in stages.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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