Revenue from contracts with customers - contract balances (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2022	Dec. 31, 2021
Revenue from Contract with Customer [Abstract]
Contract asset current	$ 4.8
Contract asset noncurrent	4.0
Receivables	824.6	$ 701.8
Receivable - increase (decrease)	122.8
Contract Assets	8.8	6.3
Contract asset increase (decrease)	2.5
Contract Liabilities	14.9	17.9
Contract liability - increase (decrease)	(3.0)
Revenue recognized included in beginning balance	9.7
Capitalized costs to obtain contracts	$ 2.3	$ 2.0

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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- Definition

Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer.

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- Definition

Amount of increase (decrease) in revenue recognized for cumulative catch-up adjustment from change in measure of progress which increases (decreases) 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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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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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, classified as current.

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- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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Amount of increase (decrease) in revenue recognized for cumulative catch-up adjustment from change in measure of progress which (increases) decreases obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

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- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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The increase (decrease) during the reporting period in amount due within one year (or one business cycle) from customers for the credit sale of goods and services.

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