Revision of Previously Issued Unaudited Financial Information (Unaudited) - Summary of Corrections to the Impacted Financial Statement Line Items (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended			6 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Jun. 30, 2025	Sep. 30, 2025	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Net loss attributable to noncontrolling interests and redeemable noncontrolling interests	$ (172)	$ (18)	$ (101)	$ (119)	$ (291)	$ (400)	$ (151)	$ (93)
Net income (loss) attributable to Clearway Energy, Inc.	232	30	(3)	27	259	169	88	79
Comprehensive loss attributable to noncontrolling interests	(174)	(27)	(104)	(131)	(305)	(404)	(151)	(97)
Comprehensive income (loss) attributable to Clearway Energy, Inc.	229	26	(5)	21	250	170	84	77
Redeemable noncontrolling interest in subsidiaries	104	45		45	104	103	0
Retained earnings	358	178	200	178	358	213	254
Noncontrolling interest	3,650	3,696	3,484	3,696	3,650	3,887	3,501
Total Stockholders’ Equity	5,685	5,535	5,420	5,535	5,685	5,811	5,564	4,994	$ 4,026
Net income (loss)						(11)	(76)	(31)
Retained Earnings
Total Stockholders’ Equity	358	178	200	178	358	213	254	361	463
Net income (loss)	232	30	(3)			169	88	79
Non-controlling Interest
Total Stockholders’ Equity	3,650	3,696	3,484	$ 3,696	$ 3,650	3,887	3,501	2,893	$ 1,792
Net income (loss)	$ (10)	$ (12)	$ (101)			(180)	(164)	(110)
Common Class A
Net income (loss) attributable to Clearway Energy, Inc.						$ 49	$ 26	$ 23
Earnings (loss) per weighted average common share - basic (in dollars per share)	$ 1.97	$ 0.25	$ (0.02)	$ 0.23	$ 2.20	$ 1.43	$ 0.75	$ 0.67
Earnings (loss) per weighted average common share - diluted (in dollars per share)	1.97	0.25	(0.02)	0.23	2.20	$ 1.43	$ 0.75	$ 0.67
Common Class C
Net income (loss) attributable to Clearway Energy, Inc.						$ 120	$ 62	$ 56
Earnings (loss) per weighted average common share - basic (in dollars per share)	1.97	0.25	(0.02)	0.23	2.20	$ 1.43	$ 0.75	$ 0.67
Earnings (loss) per weighted average common share - diluted (in dollars per share)	$ 1.97	$ 0.25	$ (0.02)	$ 0.23	$ 2.20	$ 1.43	$ 0.75	$ 0.67
As Previously Reported
Net loss attributable to noncontrolling interests and redeemable noncontrolling interests	$ (176)	$ (21)	$ (108)	$ (129)	$ (305)
Net income (loss) attributable to Clearway Energy, Inc.	236	33	4	37	273
Comprehensive loss attributable to noncontrolling interests	(178)	(30)	(111)	(141)	(319)
Comprehensive income (loss) attributable to Clearway Energy, Inc.	233	29	2	31	264
Redeemable noncontrolling interest in subsidiaries	74	38		38	74
Retained earnings	372	188	207	188	372
Noncontrolling interest	3,666	3,693	3,477	3,693	3,666
Total Stockholders’ Equity	5,715	5,542	5,420	5,542	5,715
As Previously Reported | Retained Earnings
Total Stockholders’ Equity	372	188	207	188	372
Net income (loss)	236	33	4
As Previously Reported | Non-controlling Interest
Total Stockholders’ Equity	3,666	3,693	3,477	$ 3,693	$ 3,666
Net income (loss)	$ 9	$ (8)	$ (108)
As Previously Reported | Common Class A
Earnings (loss) per weighted average common share - basic (in dollars per share)	$ 2.00	$ 0.28	$ 0.03	$ 0.31	$ 2.32
Earnings (loss) per weighted average common share - diluted (in dollars per share)	2.00	0.28	0.03	0.31	2.32
As Previously Reported | Common Class C
Earnings (loss) per weighted average common share - basic (in dollars per share)	2.00	0.28	0.03	0.31	2.32
Earnings (loss) per weighted average common share - diluted (in dollars per share)	$ 2.00	$ 0.28	$ 0.03	$ 0.31	$ 2.32
Adjustments
Net loss attributable to noncontrolling interests and redeemable noncontrolling interests	$ 4	$ 3	$ 7	$ 10	$ 14
Net income (loss) attributable to Clearway Energy, Inc.	(4)	(3)	(7)	(10)	(14)
Comprehensive loss attributable to noncontrolling interests	4	3	7	10	14
Comprehensive income (loss) attributable to Clearway Energy, Inc.	(4)	(3)	(7)	(10)	(14)
Redeemable noncontrolling interest in subsidiaries	30	7		7	30
Retained earnings	(14)	(10)	(7)	(10)	(14)
Noncontrolling interest	(16)	3	7	3	(16)
Total Stockholders’ Equity	(30)	(7)	0	(7)	(30)
Adjustments | Retained Earnings
Total Stockholders’ Equity	(14)	(10)	(7)	(10)	(14)
Net income (loss)	(4)	(3)	(7)
Adjustments | Non-controlling Interest
Total Stockholders’ Equity	(16)	3	7	$ 3	$ (16)
Net income (loss)	$ (19)	$ (4)	$ 7
Adjustments | Common Class A
Earnings (loss) per weighted average common share - basic (in dollars per share)	$ (0.03)	$ (0.03)	$ (0.05)	$ (0.08)	$ (0.12)
Earnings (loss) per weighted average common share - diluted (in dollars per share)	(0.03)	(0.03)	(0.05)	(0.08)	(0.12)
Adjustments | Common Class C
Earnings (loss) per weighted average common share - basic (in dollars per share)	(0.03)	(0.03)	(0.05)	(0.08)	(0.12)
Earnings (loss) per weighted average common share - diluted (in dollars per share)	$ (0.03)	$ (0.03)	$ (0.05)	$ (0.08)	$ (0.12)