Repurchases of Lumen Common Stock (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Equity, Class of Treasury Stock [Line Items]
Repurchase program, period (in years)	2 years
Repurchase program, authorized amount	$ 1,500			$ 1,500
Number of shares repurchased (in shares)		0	0	33,000,000
Repurchases of common stock				$ 200
Average purchase price (in dollars per share)				$ 6.07
Common Stock
Equity, Class of Treasury Stock [Line Items]
Repurchases of common stock		$ 0	$ 0	$ 33
Repurchased common stock that were retired				33
Additional Paid-in Capital
Equity, Class of Treasury Stock [Line Items]
Repurchases of common stock		$ 0	$ 0	167
Repurchased common stock that were retired				$ 167