Accounts Receivable

12 Months Ended

Dec. 31, 2021

Receivables [Abstract]

Accounts Receivable

4. Accounts Receivable

An allowance for doubtful accounts is maintained for estimated losses resulting from the inability of our customers to make required payments. Accounts receivable are stated net of the allowance for doubtful accounts of $95.4 million at December 31, 2021 ($51.3 million at December 31, 2020 and $59.9 million at December 31, 2019).