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Namespace Prefix:	clne_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

Amount of customer incentive assets.

No definition available.

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Namespace Prefix:	clne_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Amount of fuel purchases pursuant to the fuel agreement.

No definition available.

Name:	clne_FuelPurchaseObligation
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Data Type:	xbrli:monetaryItemType
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Exercise price per share or per unit of warrants or rights outstanding.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=123467817&loc=d3e21475-112644

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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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Period Type:	instant

Face amount or stated value per share of common stock.

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(29))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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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.

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Period Type:	duration

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Data Type:	na
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Data Type:	na
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Namespace Prefix:
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