Revenue from contracts with customers - contract balances (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Revenue from Contract with Customer [Abstract]
Contract asset current	$ 6.7
Contract asset noncurrent	8.7
Receivables	851.0		$ 862.2
Receivable - increase (decrease)	(11.2)
Contract Assets	15.4		12.6
Contract asset increase (decrease)	2.8
Contract Liabilities	15.0		17.0
Contract liability - increase (decrease)	(2.0)
Revenue recognized included in beginning balance	10.2
Capitalized costs to obtain contracts	3.9		$ 3.7
Capitalized cost amortization expense	$ 1.0	$ 0.6

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
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-Publisher FASB
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- Definition

Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 340
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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.

+ References

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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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.

+ References

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- Definition

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- Definition

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

+ References

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-Topic 606
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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 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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- Definition

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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- References

No definition available.

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