Debt

3 Months Ended

Mar. 31, 2022

Debt Disclosure [Abstract]

Debt

12. Debt

For both the three months ended March 31, 2022 and 2021, cash payments for interest were $7.5 million.

Included in interest expense, net is the amortization of financing costs. For the three months ended March 31, 2022 and 2021, amortization of financing costs was $0.4 million and $0.5 million, respectively.

At March 31, 2022, we had $2,491.1 million of fixed-rate senior notes outstanding. The fair value of our fixed-rate debt was estimated to be $2,395.3 million. The difference between the book value and fair value is due to the difference between the period-end market interest rate and the stated rate of our fixed-rate debt. We estimated the fair value of our fixed-rate debt using quoted market prices (Level 2 inputs) within the fair value hierarchy, which is further defined in Note 2, Summary of Significant Accounting Policies, of the Notes to Consolidated Financial Statements in "Part II, Item 8. Financial Statements and Supplementary Data" of our 2021 Annual Report on Form 10-K.

For more information on our long-term debt and interest rates on that debt, see Note 11, Debt, of the Notes to Consolidated Financial Statements in "Part II, Item 8. Financial Statements and Supplementary Data" of our 2021 Annual Report on Form 10-K.