Debt - Prior to the IPO - NuDevco Note (Details) - USD ($)	Dec. 31, 2016	Aug. 01, 2014
NuDevco Retail Holdings \| Spark HoldCo
Debt Instrument [Line Items]
Investment in affiliate transferred	$ 50,000	$ 50,000

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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