Debt Instrument, Number Of Monthly Installments

No definition available.

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Namespace Prefix:	clne_
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Balance Type:	na
Period Type:	instant

- Definition

Sale Leaseback Transaction, Purchase Price

+ References

No definition available.

+ Details

Name:	clne_SaleLeasebackTransactionPurchasePrice
Namespace Prefix:	clne_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Sale Leaseback Transaction, Rent Expense, Repayment Of Promissory Note

+ References

No definition available.

+ Details

Name:	clne_SaleLeasebackTransactionRentExpenseRepaymentOfPromissoryNote
Namespace Prefix:	clne_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Sale Leaseback Transaction, Term

+ References

No definition available.

+ Details

Name:	clne_SaleLeasebackTransactionTerm
Namespace Prefix:	clne_
Data Type:	xbrli:durationItemType
Balance Type:	na
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=114775744&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
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=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
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

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

- Definition

Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

+ 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))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Definition

Weighted average interest rate of long-term debt outstanding calculated at point in time.

+ References

No definition available.

+ Details

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

- Definition

The amount of the monthly rental payments due under the lease entered into in connection with the transactions involving the sale of property to another party and the lease of the property back to the seller.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=77913982&loc=d3e50796-112755

+ Details

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

- Definition

The amount of the current period expense recorded for use of the property in connection with the transaction involving the sale of property to another party and the lease of the property back to the seller.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41499-112717

+ Details

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

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	srt_RangeAxis=srt_MaximumMember
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- Details

Name:	us-gaap_SaleLeasebackTransactionDescriptionAxis=clne_SaleLeasebackTransactionNGAdvantageFinancingLeaseObligationMember
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- Details

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- Details

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

- Details

Name:	us-gaap_LongtermDebtTypeAxis=clne_LoanAndSecurityAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_CounterpartyNameAxis=clne_WintrustCommercialFinanceMember
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- Details

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Debt - NG Advantage Debt and Financing Lease Obligations (Details)	Dec. 20, 2018 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Jan. 24, 2017 USD ($) installment	Nov. 30, 2016 USD ($) installment	May 12, 2016 USD ($) installment
Long-term debt
Outstanding principal balance		$ 78,779,000	$ 120,388,000
Trailer and Equipment Debt
Long-term debt
Weighted average interest rate		5.58%	5.52%
Outstanding principal balance		$ 1,972,000	$ 1,786,000
Trailer and Equipment Debt \| Maximum
Long-term debt
Interest rate		6.01%
NG Advantage Financing Lease Obligation
Long-term debt
Sale leaseback transaction, purchase price	$ 7,000,000
Sale leaseback transaction, term	5 years
Sale leaseback transaction, monthly rental payments	$ 70,000
Sale leaseback transaction, rent expense	4,730,000
Sale leaseback transaction, rent expense, repayment of promissory note	$ 2,000,000
Commerce Bank & Trust Company \| 4.41% Term Loan \| Loan And Security Agreement
Long-term debt
Debt issuance amount						$ 6,300,000
Number of monthly installments \| installment						84
Interest rate						4.41%
Commerce Bank & Trust Company \| 5.0% Term Loan \| Loan And Security Agreement
Long-term debt
Debt issuance amount				$ 6,150,000
Number of monthly installments \| installment				84
Interest rate				5.00%
Wintrust Commercial Finance \| 5.17% Term Loan \| Loan And Security Agreement
Long-term debt
Debt issuance amount					$ 4,695,000
Number of monthly installments \| installment					72
Interest rate					5.17%