Derivative Instruments and Hedging Activities - Schedule of Effects of Company’s AOCI (OCL) Balance Attributable to Interest Rate Swaps Designated as Cash Flow Hedge Derivatives, Net of Tax (Details) - USD ($)
$ in Millions

Derivative Instruments and Hedging Activities - Schedule of Effects of Company’s AOCI (OCL) Balance Attributable to Interest Rate Swaps Designated as Cash Flow Hedge Derivatives, Net of Tax (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Accumulated OCI (OCL) beginning balance	$ 5,473	$ 5,535	$ 5,811	$ 5,564
Mark-to-market of cash flow hedge accounting contracts	132	(5)	161	(23)
Accumulated OCI (OCL) ending balance	5,644	5,685	5,644	5,685
Gains expected to be realized from OCI during the next 12 months, net of income tax expense of $(19)	51		51
Accumulated OCI (OCL) ending balance, net of income tax	(28)	4	(28)	4
Gains expected to be realized from OCI during the next 12 months, net of income tax expense	(19)	(19)	(19)	(19)
Accumulated Gain (Loss), Cash Flow Hedge, Including Noncontrolling Interest
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Accumulated OCI (OCL) beginning balance	24	(17)	(5)	14
Accumulated OCI (OCL) ending balance	167	(22)	167	(22)
Accumulated Foreign Currency Adjustment Including Portion Attributable to Noncontrolling Interest
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Reclassified from accumulated OCI/OCL to income due to realization of previously deferred amounts	0	(1)	1	(1)
Mark-to-market of cash flow hedge accounting contracts	132	(4)	160	(22)
Accumulated Foreign Currency Adjustment Including Portion Attributable to Noncontrolling Interest \| Rosamond South I Drop Down
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Drop Down	0	0	0	(4)
Accumulated Foreign Currency Adjustment Including Portion Attributable to Noncontrolling Interest \| Daggett 1 Drop Down
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Drop Down	0	0	0	(6)
Accumulated Foreign Currency Adjustment Including Portion Attributable to Noncontrolling Interest \| Luna Valley Drop Down
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Drop Down	0	0	0	(8)
Accumulated Foreign Currency Adjustment Including Portion Attributable to Noncontrolling Interest \| Pine Forest Drop Down
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Drop Down	0	0	0	5
Accumulated Foreign Currency Adjustment Including Portion Attributable to Noncontrolling Interest \| RS2-Spindle Drop Down
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Drop Down	11	0	11	0
Accumulated OCI (OCL) attributable to noncontrolling interests
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Accumulated OCI (OCL) ending balance	90	(9)	90	(9)
Accumulated OCI (OCL) attributable to Clearway Energy, Inc.
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Accumulated OCI (OCL) ending balance	77	(13)	77	(13)
Clearway Energy LLC \| Rosamond South I Drop Down
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Drop Down			1
Clearway Energy LLC \| Daggett 1 Drop Down
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Drop Down			4
Clearway Energy LLC \| Luna Valley Drop Down
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Drop Down			5
Clearway Energy LLC \| Pine Forest Drop Down
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Drop Down			3
Clearway Energy LLC \| RS2-Spindle Drop Down
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Drop Down			6
Noncontrolling Interest
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Accumulated OCI (OCL) beginning balance	3,622	3,696	3,887	3,501
Accumulated OCI (OCL) ending balance	$ 3,730	$ 3,650	3,730	$ 3,650
Noncontrolling Interest \| Rosamond South I Drop Down
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Drop Down			3
Noncontrolling Interest \| Daggett 1 Drop Down
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Drop Down			2
Noncontrolling Interest \| Luna Valley Drop Down
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Drop Down			3
Noncontrolling Interest \| Pine Forest Drop Down
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Drop Down			2
Noncontrolling Interest \| RS2-Spindle Drop Down
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Drop Down			$ 5