Revenue Recognition (Volume Commitment Programs) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2021	Dec. 31, 2020
Volume commitment programs
Disaggregation of Revenue [Line Items]
Commitment contract assets	$ 146.1	$ 146.1	$ 115.5
Commitment contract assets reclassified to accounts receivable	6.5	20.1
Up front customer loyalty programs and volume commitment programs
Disaggregation of Revenue [Line Items]
Estimation of future revenues	$ 2,700.0	$ 2,700.0

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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