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

No definition available.

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

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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

- Definition

Date the debt agreement requires the first payment to be made, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

Reference 2: 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

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Description of the frequency of periodic payments (monthly, quarterly, annual).

+ References

+ Details

Name:	us-gaap_DebtInstrumentFrequencyOfPeriodicPayment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

+ Details

Name:	us-gaap_DebtInstrumentMaturityDate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Description of the maturity date of the debt instrument including whether the debt matures serially and, if so, a brief description of the serial maturities.

+ References

+ Details

Name:	us-gaap_DebtInstrumentMaturityDateDescription
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

+ References

+ Details

Name:	us-gaap_LongTermDebtPercentageBearingFixedInterestRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3291-108585

+ Details

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

- Definition

Percentage of an entity's outstanding debt that is designated as a hedged item in cash flow, fair value, or net investment hedge.

+ References

No definition available.

+ Details

Name:	us-gaap_PercentageOfDebtHedgedByInterestRateDerivatives
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
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

No definition available.

+ Details

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

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Additional availability period.

+ References

No definition available.

+ Details

Name:	vslr_AdditionalAvailabilityPeriod
Namespace Prefix:	vslr_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Availability period end date.

+ References

No definition available.

+ Details

Name:	vslr_AvailabilityPeriodEndDate
Namespace Prefix:	vslr_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt service coverage ratios.

+ References

No definition available.

+ Details

Name:	vslr_DebtServiceCoverageRatios
Namespace Prefix:	vslr_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt service reserve account.

+ References

No definition available.

+ Details

Name:	vslr_DebtServiceReserveAccount
Namespace Prefix:	vslr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Payment of insurance premium.

+ References

No definition available.

+ Details

Name:	vslr_PaymentOfInsurancePremium
Namespace Prefix:	vslr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Retained proceeds from lines of credit.

+ References

No definition available.

+ Details

Name:	vslr_RetainedProceedsFromLinesOfCredit
Namespace Prefix:	vslr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_CreditFacilityAxis=vslr_AmendedBankOfAmericaAggregationCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementScenarioAxis=us-gaap_ScenarioForecastMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=vslr_BankOfAmericaAggregationCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=vslr_TwoThousandSeventeenTermLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Subsequent Events - Additional Information (Details) - USD ($) $ in Thousands				1 Months Ended	12 Months Ended
	Apr. 01, 2020	Mar. 09, 2017	Jan. 05, 2017	Aug. 31, 2016	Dec. 31, 2016	Dec. 31, 2015
Subsequent Event [Line Items]
Debt instrument borrowings under credit agreement					$ 771,852	$ 415,850
Amended Bank Of America Aggregation Credit Facility \| Scenario, Forecast \| Minimum
Subsequent Event [Line Items]
Debt instrument interest rate	3.50%
Amended Bank Of America Aggregation Credit Facility \| Scenario, Forecast \| Maximum
Subsequent Event [Line Items]
Debt instrument interest rate	3.75%
Bank Of America Aggregation Credit Facility
Subsequent Event [Line Items]
Debt instrument borrowings under credit agreement					$ 187,000	$ 269,100
Repayment of existing indebtedness				$ 220,500
Maturity Date					Mar. 12, 2018	Mar. 12, 2018
Bank Of America Aggregation Credit Facility \| Minimum
Subsequent Event [Line Items]
Debt instrument interest rate					3.25%
Bank Of America Aggregation Credit Facility \| Maximum
Subsequent Event [Line Items]
Debt instrument interest rate					3.50%
2017 Term Loan
Subsequent Event [Line Items]
Debt instrument final maturity date, description					Principal and interest payable under the 2017 Term Loan will be paid over the term of the loan until the final maturity date of January 5, 2035
Subsequent Event \| Amended Bank Of America Aggregation Credit Facility
Subsequent Event [Line Items]
Maturity Date		Sep. 30, 2020
Availability period end date		Mar. 31, 2020
Extendable additional availability period to the extent the lenders		12 months
Debt instrument interest rate		3.25%
Subsequent Event \| Bank Of America Aggregation Credit Facility \| Maximum
Subsequent Event [Line Items]
Percentage of outstanding loan balances to be hedged		75.00%
Subsequent Event \| 2017 Term Loan
Subsequent Event [Line Items]
Debt instrument borrowings under credit agreement			$ 203,800
Repayment of existing indebtedness			140,300
Debt service reserve account			20,100
Debt transaction costs and fees			5,500
Payment of insurance premium			2,000
Distribution to reimbursement of capital costs			$ 35,900
Interest on borrowings accrue at an annual fixed rate and payable in arrears			6.00%
Debt instrument, frequency of periodic payment			Quarterly basis
Debt instrument date of first principal and interest payment			Apr. 30, 2017
Maturity Date			Jan. 05, 2035
Debt service coverage ratios			120.00%