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

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Gross amount of debt extinguished.

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Long-Term Debt and Credit Facilities - Borrowings and Repayments (Details) - USD ($) $ in Millions			12 Months Ended
	Jun. 15, 2021	Jan. 13, 2021	Dec. 31, 2022	Dec. 31, 2021	Jun. 30, 2021
Long-term Debt and Credit Facilities
Borrowings			$ 2,400	$ 400
Repayments of debt			2,600	350
Gain (loss) on extinguishment of debt			$ 214	$ 8
Senior notes \| 5.375% Senior Notes due 2029
Long-term Debt and Credit Facilities
Stated interest rate			5.375%
Senior notes \| 6.450% Senior Notes, Series S, due 2021 (at maturity)
Long-term Debt and Credit Facilities
Stated interest rate	6.45%				6.45%
Amount of debt redeemed	$ 1,200
Senior notes \| 5.375% Senior Notes due 2029
Long-term Debt and Credit Facilities
Debt instrument, face amount	$ 1,000
Stated interest rate	5.375%
Senior notes \| Level 3 Financing, Inc.
Long-term Debt and Credit Facilities
Amount of debt redeemed		$ 900
Senior notes \| Level 3 Financing, Inc. \| 3.750% Sustainability-Linked Senior Notes 2029
Long-term Debt and Credit Facilities
Debt instrument, face amount		$ 900
Stated interest rate		3.75%