Long-Term Debt	3 Months Ended
Mar. 31, 2022
Debt Disclosure [Abstract]
Long-Term Debt	7. Long-Term Debt Fair Value of Long-Term Debt At March 31, 2022, TEC’s long-term debt, including the current portion, had a carrying amount of $3,387 million and an estimated fair market value of $3,551 million. At December 31, 2021, TEC’s total long-term debt, including the current portion, had a carrying amount of $3,386 million and an estimated fair market value of $4,036 million. The fair value of the debt securities is determined using Level 2 measurements (see Note 11 for information regarding the fair value hierarchy).

Long-Term Debt

3 Months Ended

Mar. 31, 2022

7. Long-Term Debt

Fair Value of Long-Term Debt

At March 31, 2022, TEC’s long-term debt, including the current portion, had a carrying amount of $3,387 million and an estimated fair market value of $3,551 million. At December 31, 2021, TEC’s total long-term debt, including the current portion, had a carrying amount of $3,386 million and an estimated fair market value of $4,036 million. The fair value of the debt securities is determined using Level 2 measurements (see Note 11 for information regarding the fair value hierarchy).