Financial Instruments	9 Months Ended
Sep. 30, 2021
Financial Instruments[Abstract]
Financial Instruments	13. Financial Instruments Short-Term Investments – All of the Company’s short-term investments consist of time deposits and government agency securities. These investments are considered Level 2 investments and are valued at amortized cost, which approximates fair value. As of September 30, 2021, the Company had $46 million of short-term investments. All short-term investments have a maturity of less than one year and are classified as held-to-maturity. Fair Value of Financial Instruments – The fair value of our short- and long-term debt was estimated using a market value price model, which utilizes applicable U.S. Treasury rates along with current market quotes on comparable debt securities. All of the inputs used to determine the fair market value of the Corporation’s long-term debt are Level 2 inputs and obtained from an independent source. At September 30, 2021, the fair value of total debt was $32.8 billion, approximately $3.4 billion more than the carrying value. At December 31, 2020, the fair value of total debt was $31.9 billion, approximately $5.1 billion more than the carrying value. The fair value of the Corporation’s debt is a measure of its current value under present market conditions. The fair value of our cash equivalents approximates their carrying value due to the short-term maturities of these instruments. We have equity investments that are carried at fair value with changes in unrealized gains and losses recognized in other income on our Condensed Consolidated Statements of Income. These investments are valued based on quoted prices in active markets for publicly traded securities and are classified in Level 1 of the fair value hierarchy. We recorded an unrealized loss of $12 million and a gain of $8 million during the three and nine months ended September 30, 2021, respectively.

Financial Instruments

9 Months Ended

Sep. 30, 2021

13. Financial Instruments

Short-Term Investments – All of the Company’s short-term investments consist of time deposits and government agency securities. These investments are considered Level 2 investments and are valued at amortized cost, which approximates fair value. As of September 30, 2021, the Company had $46 million of short-term investments. All short-term investments have a maturity of less than one year and are classified as held-to-maturity.

Fair Value of Financial Instruments – The fair value of our short- and long-term debt was estimated using a market value price model, which utilizes applicable U.S. Treasury rates along with current market quotes on comparable debt securities. All of the inputs used to determine the fair market value of the Corporation’s long-term debt are Level 2 inputs and obtained from an independent source. At September 30, 2021, the fair value of total debt was $32.8 billion, approximately $3.4 billion more than the carrying value. At December 31, 2020, the fair value of total debt was $31.9 billion, approximately $5.1 billion more than the carrying value. The fair value of the Corporation’s debt is a measure of its current value under present market conditions. The fair value of our cash equivalents approximates their carrying value due to the short-term maturities of these instruments.

We have equity investments that are carried at fair value with changes in unrealized gains and losses recognized in other income on our Condensed Consolidated Statements of Income. These investments are valued based on quoted prices in active markets for publicly traded securities and are classified in Level 1 of the fair value hierarchy. We recorded an unrealized loss of $12 million and a gain of $8 million during the three and nine months ended September 30, 2021, respectively.