Fair Value Measurement - Contingent Consideration (Details) - Omni Energy, LLC $ in Thousands	5 Months Ended
Dec. 31, 2019 USD ($)
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration [Abstract]
Balance recorded in connection with business acquisition	$ 20,800
Gains recognized in earnings within sales and marketing expense	(2,271)
Payable for solar systems that have met deployment milestones	(6,720)
Balance at December 31, 2019	$ 11,809

Amount of liability recognized arising from contingent consideration in a business combination.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 35
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=116859824&loc=d3e6819-128478

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 25
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6408-128476

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