Debt Instrument, Discount Rate

No definition available.

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- Definition

The value of the financial instrument(s) that the original debt is being converted into in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=121583591&loc=d3e4304-108586

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=121583591&loc=d3e4332-108586

+ Details

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

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28551-108399

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-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

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

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
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Data Type:	num:percentItemType
Balance Type:	na
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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3291-108585

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_LineOfCreditMember
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Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
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Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=nova_SunnovaTEPHoldingsLLCMember
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Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=nova_SunnovaAssetPortfolio8LLCMember
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- Details

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Data Type:	na
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- Details

Name:	us-gaap_LongtermDebtTypeAxis=nova_ConvertibleSeniorNotesMember
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- Details

Name:	us-gaap_DebtInstrumentAxis=nova_NinePointSevenFiveConvertibleSeniorNotesDueAprilTwentyTwentyFiveMember
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- Details

Name:	dei_LegalEntityAxis=nova_HeliosVIssuerLLCMember
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- Details

Name:	us-gaap_LongtermDebtTypeAxis=nova_LoanBackedNotesMember
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- Details

Name:	us-gaap_DebtInstrumentAxis=nova_HELVSeries2021AClassAMember
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- Details

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Long-Term Debt - Narrative (Details) - USD ($)	1 Months Ended	3 Months Ended
Long-Term Debt - Narrative (Details) - USD ($)	Feb. 28, 2021	Mar. 31, 2021	Mar. 31, 2020	Mar. 30, 2021
Debt Instrument [Line Items]
Borrowing capacity		$ 281,100,000
Debt conversion		95,648,000	$ 0
EZOP \| Line of Credit \| Revolving credit facility
Debt Instrument [Line Items]
Borrowing capacity		90,600,000
Repayments of debt	$ 107,300,000
Maximum borrowing capacity		350,000,000.0		$ 200,000,000.0
TEPH \| Line of Credit \| Revolving credit facility
Debt Instrument [Line Items]
Borrowing capacity		156,100,000
AP8 \| Line of Credit \| Revolving credit facility
Debt Instrument [Line Items]
Borrowing capacity		$ 34,400,000
Repayments of debt	$ 29,500,000
SEI \| Convertible senior notes \| 9.75% convertible senior notes
Debt Instrument [Line Items]
Stated interest rate		9.75%
Debt conversion		$ 97,100,000
HELV \| Solar loan-backed notes \| HELV Series 2021-A Class A
Debt Instrument [Line Items]
Stated interest rate	1.80%
Principal amount of debt issued	$ 150,100,000
Discount percent	0.001%
HELV \| Solar loan-backed notes \| HELV Series 2021-A Class B
Debt Instrument [Line Items]
Stated interest rate	3.15%
Principal amount of debt issued	$ 38,600,000
Discount percent	2.487%