Credit Losses (Tables)

3 Months Ended

Mar. 31, 2022

Credit Loss [Abstract]

Accounts Receivable, Allowance for Credit Loss

Changes in the allowance for doubtful accounts balance were as follows:    

(In millions)	March 31, 2022		December 31, 2021
Beginning balance as of January 1	$	15	$	22
Current period provision	—		3
Current period write offs	—		(5)
Recoveries of amounts previously reserved	—		(5)
Ending balance	$	15	$	15