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.

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	duration

- Definition

The amount of excise and sales taxes included in sales and revenues, which are then deducted as a cost of sales. Includes excise taxes, which are applied to specific types of transactions or items (such as gasoline or alcohol); and sales, use and value added taxes, which are applied to a broad class of revenue-producing transactions involving a wide range of goods and services.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(1))
-URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227

+ Details

Name:	us-gaap_ExciseAndSalesTaxes
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Description of timing for satisfying performance obligation in contract with customer. Includes, but is not limited to, as services are rendered, and upon shipment, delivery or completion of service.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130554-203045

+ Details

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Period Type:	duration

- Details

Name:	us-gaap_IncomeStatementLocationAxis=spke_ElectricAndGasRevenueMember
Namespace Prefix:
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Period Type:

- Details

Name:	us-gaap_IncomeStatementLocationAxis=spke_CostOfServicesEnergyServicesMember
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Revenues - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
Revenues - Narrative (Details) - USD ($) $ in Millions	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Typical length of contract			Electricity and natural gas products may be sold as fixed-price or variable-price products. The typical length of a contract to provide electricity and/or natural gas is twelve months.
Electric and Gas Revenue
Disaggregation of Revenue [Line Items]
Excise and sales taxes	$ 0.3	$ 0.3	$ 0.8	$ 1.0
Cost of Services Energy Services
Disaggregation of Revenue [Line Items]
Excise and sales taxes	$ 1.2	$ 1.6	$ 3.4	$ 4.7