Debt

3 Months Ended

Mar. 31, 2021

Credit Facilities

As of March 31, 2021 and December 31, 2020, we had $1.5 billion available under a revolving credit facility (the “Revolver”) pursuant to a credit agreement entered into on October 11, 2013 (as amended thereafter and from time to time, the “Credit Agreement”). To date, we have not drawn on the Revolver and we were in compliance with the terms of the Credit Agreement as of March 31, 2021.

Refer to Note 13 contained in our Annual Report on Form 10-K for the year ended December 31, 2020 for further details regarding the Credit Agreement and its key terms.

Unsecured Senior Notes

As of March 31, 2021 and December 31, 2020, we had $3.7 billion of gross unsecured senior notes outstanding. A summary of our outstanding unsecured senior notes is as follows (amounts in millions):


				At March 31, 2021			At December 31, 2020
Unsecured Senior Notes	Interest Rate	Semi-Annual Interest Payments Due On	Maturity	Principal		Fair Value (Level 2)	Principal		Fair Value (Level 2)
2026 Notes	3.40%	Mar. 15 & Sept. 15	Sept. 2026	850		930	850		970
2027 Notes	3.40%	Jun. 15 & Dec. 15	Jun. 2027	400		438	400		454
2030 Notes	1.35%	Mar. 15 & Sept. 15	Sept. 2030	500		450	500		490
2047 Notes	4.50%	Jun. 15 & Dec. 15	Jun. 2047	400		469	400		525
2050 Notes	2.50%	Mar. 15 & Sept. 15	Sept. 2050	1,500		1,258	1,500		1,462
Total gross long-term debt				$	3,650		$	3,650
Unamortized discount and deferred financing costs				(44)			(45)
Total net carrying amount				$	3,606		$	3,605

We were in compliance with the terms of the notes outstanding as of March 31, 2021. As of March 31, 2021, we have no contractual principal repayments of our long-term debt due within the next five years.

Refer to Note 13 contained in our Annual Report on Form 10-K for the year ended December 31, 2020 for further details regarding key terms under our indentures that govern our outstanding notes.