Debt Instrument, Debt Covenant, Adjusted Tangible Net Worth, Aggregate Commitments Percentage

No definition available.

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- Definition

Debt Instrument, Debt Covenant, Adjusted Tangible Net Worth, Borrowings Percentage

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Debt Covenant, Adjusted Tangible Net Worth, Greater than, Threshold

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No definition available.

+ Details

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- Definition

Debt Instrument, Debt Covenant, Leverage Ratio, Maximum

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No definition available.

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- Definition

Debt Instrument, Debt Covenant, Minimum Fixed Charge Coverage Ratio

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No definition available.

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- Definition

Debt Instrument, Debt Covenant, Working Capital, Increase Maximum

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No definition available.

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- Definition

Debt Instrument, Debt Covenant, Working Capital, Percentage of Borrowing Capacity

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No definition available.

+ Details

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- Definition

Debt Instrument, Debt Default, Change in Control, Ownership Percentage, Minimum

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No definition available.

+ Details

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Period Type:	duration

- Definition

Debt Instrument, Debt Default, Material Judgements, Maximum

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No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Debt Instrument, Reduction In Interest Rate If Facility Utilization Less Than Fifty Percent

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No definition available.

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Period Type:	duration

- Definition

Line Of Credit Facility, Contingent Maximum Borrowing Capacity

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No definition available.

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Namespace Prefix:	spke_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line of Credit Facility, Annual Payment Percentage

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of Credit Facility, Balloon Payment to be Paid Percentage

+ References

No definition available.

+ Details

Name:	spke_LineofCreditFacilityBalloonPaymenttobePaidPercentage
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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of Credit Facility, Borrowing Base Calculated as Percentage of Accounts Receivable, Unbilled Product Sales, Inventory, Other Working Capital Assets

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of Credit Facility, Fair Value of Amount Outstanding, Portion Paid By Affiliate

+ References

No definition available.

+ Details

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Namespace Prefix:	spke_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line of Credit Facility, Financing of Business Combination, Maximum Percentage

+ References

No definition available.

+ Details

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Namespace Prefix:	spke_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of Credit Facility Minimum Borrowing Capacity

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No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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- Details

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Debt - Senior Credit Facility Executed at the IPO and Senior Credit Facility (Details) - USD ($)					9 Months Ended
	Mar. 31, 2017	Jul. 08, 2015	Jul. 31, 2013	Dec. 17, 2012	Sep. 30, 2016	Dec. 31, 2016	Oct. 01, 2016	Sep. 29, 2016	Aug. 01, 2016	Jun. 01, 2016	May 31, 2016	Dec. 31, 2015	Aug. 01, 2014	Dec. 31, 2013	Dec. 31, 2012
Senior Secured Revolving Credit Facility
Line of Credit Facility [Line Items]
Line of credit facility, minimum borrowing capacity		$ 5,000,000.0
Adjusted tangible net worth threshold (greater than)		$ 18,000,000.0
Minimum fixed charge coverage ratio		120.00%
Maximum leverage ratio		250.00%
Debt default, change in control, ownership percentage (less than)		40.00%
Debt default, material judgment (in excess of)		$ 5,000,000.0
Senior Credit Facility
Line of Credit Facility [Line Items]
Letters of credit issued and outstanding						$ 29,600,000						$ 21,500,000
Revolving Credit Facility \| Senior Secured Revolving Credit Facility \| Maximum
Line of Credit Facility [Line Items]
Commitment fee percentage		0.50%
Revolving Credit Facility \| Senior Secured Revolving Credit Facility \| Minimum
Line of Credit Facility [Line Items]
Commitment fee percentage		0.375%
Revolving Credit Facility \| Senior Secured Revolving Credit Facility \| Eurodollar \| Maximum
Line of Credit Facility [Line Items]
Basis spread on variable rate		3.00%
Revolving Credit Facility \| Senior Secured Revolving Credit Facility \| Base Rate \| Maximum
Line of Credit Facility [Line Items]
Basis spread on variable rate		2.00%
Revolving Credit Facility \| Senior Secured Revolving Credit Facility \| Cost of Funds Rate \| Maximum
Line of Credit Facility [Line Items]
Basis spread on variable rate		2.50%
Revolving Credit Facility \| Working Capital Line
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity		$ 60,000,000.0			$ 82,500,000.0	$ 70,000,000.0	$ 60,000,000.0	$ 82,500,000.0		$ 82,500,000.0	$ 60,000,000.0
Line of credit facility, minimum borrowing capacity									$ 40,000,000
Working capital, maximum increase		$ 5,000,000.0
Working capital, percentage of borrowing capacity		15.00%
Adjusted tangible net worth, aggregate commitments percentage		20.00%
Revolving Credit Facility \| Working Capital Line \| Maximum
Line of Credit Facility [Line Items]
Line of credit, availability		$ 82,500,000.0
Borrowing base calculated on value of eligible accounts receivable, unbilled product sales, inventory and other working capital assets, percentage		90.00%
Revolving Credit Facility \| Working Capital Line \| Minimum
Line of Credit Facility [Line Items]
Line of credit, availability		$ 40,000,000.0
Borrowing base calculated on value of eligible accounts receivable, unbilled product sales, inventory and other working capital assets, percentage		80.00%
Revolving Credit Facility \| Working Capital Line \| Federal Funds Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate		0.50%
Revolving Credit Facility \| Working Capital Line \| Reference Eurodollar Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate		1.00%
Revolving Credit Facility \| Acquisition Line
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity		$ 25,000,000.0			$ 25,000,000.0
Financing of cost of acquisitions, maximum percentage		75.00%			75.00%
Annual payment percentage		25.00%
Remaining payment due at maturity, percentage		50.00%
Nonutilization fee		0.50%
Adjusted tangible net worth, borrowings percentage		33.00%
Revolving Credit Facility \| Acquisition Line \| Eurodollar
Line of Credit Facility [Line Items]
Basis spread on variable rate		3.75%
Revolving Credit Facility \| Acquisition Line \| Base Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate		2.75%
Revolving Credit Facility \| Acquisition Line \| Federal Funds Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate		0.50%
Revolving Credit Facility \| Acquisition Line \| Reference Eurodollar Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate		1.00%
Revolving Credit Facility \| Senior Credit Facility \| Senior Secured Revolving Credit Facility
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity													$ 70,000,000.0
Contingent maximum borrowing capacity													120,000,000.0
Line of credit facility, outstanding													10,000,000
Reduction to interest rate if facility utilization is less than fifty percent		25.00%
Working Capital Facility
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity			$ 80,000,000	$ 70,000,000											$ 150,000,000
Working capital credit facility outstanding portion paid by affiliate														$ 29,000,000
Commitment fee percentage			0.50%
Nonutilization fee				0.50%
Working Capital Facility \| Eurodollar \| Maximum
Line of Credit Facility [Line Items]
Basis spread on variable rate			3.25%	3.75%
Working Capital Facility \| Eurodollar \| Minimum
Line of Credit Facility [Line Items]
Basis spread on variable rate			3.00%	3.00%
Working Capital Facility \| Base Rate \| Maximum
Line of Credit Facility [Line Items]
Basis spread on variable rate			2.25%	2.75%
Working Capital Facility \| Base Rate \| Minimum
Line of Credit Facility [Line Items]
Basis spread on variable rate			2.00%	2.00%
Working Capital Facility \| Cost of Funds Rate \| Maximum
Line of Credit Facility [Line Items]
Basis spread on variable rate			2.75%
Working Capital Facility \| Cost of Funds Rate \| Minimum
Line of Credit Facility [Line Items]
Basis spread on variable rate			2.50%
Working Capital Facility \| Senior Credit Facility
Line of Credit Facility [Line Items]
Working capital credit facility outstanding portion paid by affiliate													29,000,000
Letters of credit issued and outstanding													$ 15,000,000
Scenario, Forecast \| Senior Secured Revolving Credit Facility
Line of Credit Facility [Line Items]
Minimum fixed charge coverage ratio	125.00%