Balance Sheet Components - Goodwill (Details) - USD ($)	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Goodwill
Beginning balance		$ 5,210,821	$ 0	$ 0
Goodwill acquired in conjunction with the Napo merger		0		22,037,821
Impairment	$ (3,648,000)		$ (3,648,000)	(16,827,000)
Ending balance		$ 5,210,821		$ 5,210,821

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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