v3.25.3

Changes in Capital Structure - Treasury Stock Retirements (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended						9 Months Ended
	Jul. 08, 2025	Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2025	Sep. 30, 2024
Equity, Class of Treasury Stock [Line Items]
Retirement of treasury stock (in shares)	224,585
Treasury Stock
Equity, Class of Treasury Stock [Line Items]
Retirement of treasury stock (in shares)		1,513,739	2,443,610	3,070,996	2,833,382	1,114,400	1,163,230	7,028,345	5,111,012
Average price paid per share (in usd per share)		$ 83.45	$ 73.01	$ 58.23	$ 35.40	$ 33.84	$ 32.67
Retirement of treasury stock		$ 126	$ 178	$ 179	$ 100	$ 38	$ 38	$ 483	$ 176

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.

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

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-Topic 505
-SubTopic 30
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- Definition

Amount of decrease of par value, additional paid in capital (APIC) and retained earnings of common and preferred stock retired from treasury when treasury stock is accounted for under the cost method.

+ References

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Number of shares of common and preferred stock retired from treasury during the period.

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NRG ENERGY, INC. 10-Q