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

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- Definition

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

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

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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.

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No definition available.

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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- Definition

Fair value amount of debt instrument that was repurchased.

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No definition available.

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Face (par) amount of the original debt instrument that was repurchased.

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No definition available.

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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders.

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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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

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Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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The cash outflow for a long-term debt where the holder has highest claim on the entity's asset in case of bankruptcy or liquidation during the period.

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Long-term Debt - Debt Disclosures (Details) - USD ($) $ in Millions							1 Months Ended	3 Months Ended			9 Months Ended
	Nov. 02, 2020	Sep. 30, 2020	Sep. 01, 2020	Jun. 01, 2020	May 21, 2020	Jan. 03, 2020	Feb. 29, 2020	Sep. 30, 2020	Sep. 30, 2019	Jun. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Debt Instrument [Line Items]
Proceeds from the revolving credit facility											$ 265.0	$ 22.0
Payments for the revolving credit facility											265.0	22.0
Loss on debt extinguishment								$ 6.0	$ 0.0		9.0	$ 1.0
Distributions									$ 4.0	$ 30.0
DG-CS Master Borrower LLC \| Subsequent Event
Debt Instrument [Line Items]
Unwind related to derivatives	$ 42.0
Clearway Energy LLC and Clearway Energy Operating LLC Revolving Credit Facility, due 2023
Debt Instrument [Line Items]
Proceeds from the revolving credit facility											265.0
Payments for the revolving credit facility											$ 265.0
Clearway Energy LLC and Clearway Energy Operating LLC Revolving Credit Facility, due 2023 \| LIBOR
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate											2.00%
2024 Senior Notes
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage		5.375%						5.375%			5.375%
Construction Debt
Debt Instrument [Line Items]
Repayments of debt							$ 260.0
CS4 Borrower, due 2026 \| LIBOR
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate											2.00%
CS4 Borrower, due 2026 \| LIBOR \| Renew CS4 Borrower LLC
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate								2.00%
CS4 Borrower, due 2026 \| Conversion period one \| Renew CS4 Borrower LLC
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage		2.00%						2.00%			2.00%
CS4 Borrower, due 2026 \| Conversion period two \| Renew CS4 Borrower LLC
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage		2.25%						2.25%			2.25%
Chestnut Borrower, LLC \| Subsequent Event
Debt Instrument [Line Items]
Repayments of debt	107.0
Renew Solar CS 4 Borrower LLC \| Subsequent Event
Debt Instrument [Line Items]
Repayments of debt	102.0
DGPV 4 Borrower LLC \| Subsequent Event
Debt Instrument [Line Items]
Repayments of debt	92.0
Puma Class B LLC \| Subsequent Event
Debt Instrument [Line Items]
Repayments of debt	$ 73.0
Utah Solar Holdings, due 2036
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate											3.59%
DG-CS Master Borrower LLC Financing Arrangement \| DG-CS Master Borrower LLC \| Subsequent Event
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	3.51%
Letter of Credit \| Clearway Energy LLC and Clearway Energy Operating LLC Revolving Credit Facility, due 2023
Debt Instrument [Line Items]
Letters of credit outstanding, amount		$ 59.0						$ 59.0			$ 59.0
Letter of Credit \| CS4 Borrower, due 2026
Debt Instrument [Line Items]
Letters of credit outstanding, amount		4.0						4.0			4.0
Letter of Credit \| CS4 Borrower, due 2026 \| Renew CS4 Borrower LLC
Debt Instrument [Line Items]
Debt amount (up to)		4.9						4.9			4.9
Letter of Credit \| Chestnut Borrower credit agreement \| Chestnut Borrower, LLC
Debt Instrument [Line Items]
Debt amount (up to)		7.9						7.9			7.9
Letter of Credit \| Utah Solar Holdings, due 2036
Debt Instrument [Line Items]
Letters of credit outstanding, amount		9.0						9.0			9.0
Letter of Credit \| Utah Solar Holdings, due 2036 \| Utah Solar Holdings, LLC
Debt Instrument [Line Items]
Proceeds from the revolving credit facility			$ 16.0
Letter of Credit \| DG-CS Master Borrower LLC Financing Arrangement \| DG-CS Master Borrower LLC \| Subsequent Event
Debt Instrument [Line Items]
Proceeds from the revolving credit facility	$ 30.0
Letter of Credit \| NIMH Solar LLC Financing Arrangement \| NIMH Solar LLC
Debt Instrument [Line Items]
Proceeds from the revolving credit facility		16.0
Construction loans \| CS4 Borrower, due 2026 \| Renew CS4 Borrower LLC
Debt Instrument [Line Items]
Debt amount (up to)		97.4						97.4			97.4
ITC bridge loan \| CS4 Borrower, due 2026 \| Renew CS4 Borrower LLC
Debt Instrument [Line Items]
Debt amount (up to)		89.9						89.9			89.9
Term loan \| Chestnut Borrower credit agreement \| Chestnut Borrower, LLC
Debt Instrument [Line Items]
Debt amount (up to)		120.3						$ 120.3			$ 120.3
Term loan \| Chestnut Borrower credit agreement \| Conversion period one \| LIBOR \| Chestnut Borrower, LLC
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate								2.50%
Term loan \| Chestnut Borrower credit agreement \| Conversion period two \| LIBOR \| Chestnut Borrower, LLC
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate								2.75%
Term loan \| Project level debt \| Alpine
Debt Instrument [Line Items]
Repayments of debt		117.0
Term loan \| Project level debt \| Blythe
Debt Instrument [Line Items]
Repayments of debt		14.0
Term loan \| Project level debt \| Roadrunner
Debt Instrument [Line Items]
Repayments of debt		27.0
Term loan \| DG-CS Master Borrower LLC Financing Arrangement \| DG-CS Master Borrower LLC \| Subsequent Event
Debt Instrument [Line Items]
Proceeds from the revolving credit facility	$ 467.0
Term loan \| NIMH Solar LLC Financing Arrangement \| Affiliated Entity \| Clearway Energy Operating LLC
Debt Instrument [Line Items]
Distributions		45.0
Term loan \| NIMH Solar LLC Financing Arrangement \| NIMH Solar LLC
Debt Instrument [Line Items]
Proceeds from the revolving credit facility		$ 193.0
Term loan \| NIMH Solar LLC Financing Arrangement \| LIBOR \| Through Third Party Anniversary of Closing
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage		2.00%						2.00%			2.00%
Term loan \| NIMH Solar LLC Financing Arrangement \| LIBOR \| After Third Party Anniversary of Closing
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage		2.125%						2.125%			2.125%
Senior Notes \| 2024 Senior Notes
Debt Instrument [Line Items]
Debt instrument, redemption price, percentage						102.70%
Debt instrument, repurchased face amount						$ 88.0
Debt instrument, repurchase amount						90.0
Loss on debt extinguishment						$ (3.0)
Senior Notes \| 4.75% Senior Notes due in 2028
Debt Instrument [Line Items]
Debt amount (up to)					$ 250.0
Debt instrument, interest rate, stated percentage					4.75%
Debt instrument, redemption price, percentage					102.00%
Repayment of outstanding principal amount				$ 45.0
Senior Notes \| Utah Solar Holdings, due 2036 \| Utah Solar Holdings, LLC
Debt Instrument [Line Items]
Proceeds from the revolving credit facility			$ 296.0
Debt instrument, interest rate, stated percentage			3.59%
Repayments of debt			$ 247.0
Unwind related to derivatives			33.0
Senior Notes \| Utah Solar Holdings, due 2036 \| Utah Solar Holdings, LLC \| Affiliated Entity \| Clearway Energy Operating LLC
Debt Instrument [Line Items]
Distributions			$ 9.0