Fair Value of Financial Instruments (Tables)

3 Months Ended

Mar. 31, 2020

Fair Value Disclosures [Abstract]

Schedule of Carrying Amounts and Estimated Fair Values of Long-term Debt, Excluding Capital Lease Obligations, and Input Level to Determine Fair Values

The following table presents the carrying amounts and estimated fair values of our financial liabilities as of March 31, 2020 and December 31, 2019:

		March 31, 2020			December 31, 2019
	Input Level	Carrying Amount		Fair Value	Carrying Amount	Fair Value
		(Dollars in millions)
Long-term debt, excluding finance lease and other obligations	2	$	34,405	33,117	34,472	35,737
Interest rate swap contracts (see Note 10)	2	152		152	51	51