Power Generation Capacity, Megawatts

No definition available.

Name:	cwen_PowerGenerationCapacityMegawatts
Namespace Prefix:	cwen_
Data Type:	num:powerItemType
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:	srt_CondensedCashFlowStatementsCaptionsLineItems
Namespace Prefix:	srt_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

+ Details

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

- Definition

Percentage investment held by members or limited partners of limited liability company (LLC) or limited partnership (LP).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

+ Details

Name:	us-gaap_LimitedLiabilityCompanyLLCOrLimitedPartnershipLPMembersOrLimitedPartnersOwnershipInterest
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Dividends received on equity and other investments during the current period.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 16
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3337-108585

+ Details

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

- Details

Name:	srt_OwnershipAxis=cwen_ClearwayEnergyLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=cwen_ClearwayEnergyInc.Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_OwnershipAxis=cwen_GIPMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=cwen_ClearwayEnergyLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_OwnershipAxis=cwen_ClearwayEnergyInc.Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=cwen_CarlsbadDropDownMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	cwen_PowerGenerationFacilitiesByTypeAxis=cwen_ConventionalGenerationUtilityScaleSolarDistributedSolarandWindMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	cwen_PowerGenerationFacilitiesByTypeAxis=srt_NaturalGasReservesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Schedule I - Condensed Financial Information of Registrant - Footnotes (Details) $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($) MW	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 06, 2019 MW	Aug. 31, 2018	Mar. 30, 2018
Condensed Cash Flow Statements, Captions [Line Items]
Ownership interest acquired						100.00%
Cash distributions \| $	$ 121	$ 87	$ 130
Clearway Energy LLC
Condensed Cash Flow Statements, Captions [Line Items]
Limited liability company or limited partnership, members or limited partners, ownership interest	57.61%
Clearway Energy, Inc. \| GIP
Condensed Cash Flow Statements, Captions [Line Items]
Ownership interest acquired					55.00%
Clearway Energy LLC \| GIP
Condensed Cash Flow Statements, Captions [Line Items]
Ownership interest acquired					45.20%
Clearway Energy LLC \| Clearway Energy, Inc.
Condensed Cash Flow Statements, Captions [Line Items]
Limited liability company or limited partnership, members or limited partners, ownership interest	57.61%
Carlsbad Drop Down
Condensed Cash Flow Statements, Captions [Line Items]
Ownership interest acquired				100.00%
Conventional Generation, Utility-Scale Solar, Distributed Solar, and Wind
Condensed Cash Flow Statements, Captions [Line Items]
Power generation capacity, megawatts	4,200
Natural Gas \| Carlsbad Drop Down
Condensed Cash Flow Statements, Captions [Line Items]
Power generation capacity, megawatts				527