Revenue Recognition - Contract Liabilities (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Apr. 01, 2018	Jan. 01, 2019	Jan. 01, 2018
Contract with Customer, Asset
Contract Assets	$ 0.3	$ 1.7	$ 1.0	$ 0.6
Change in period	(0.7)	1.1
Contract Liabilities
Contract Liabilities - Current	11.4	11.5	11.3	11.3
Increase (decrease) - Current Liabilities	0.1	0.2
Current Liabilities - Noncurrent	2.7	2.4	$ 2.7	$ 2.1
Increase (decrease) - Noncurrent Liabilities		$ 0.3
Revenue recognized, contract liability	3.3
Impairment loss related to Contract Assets	$ 0.0

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

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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 of revenue recognized arising from contract liability from change in timeframe for performance obligation to be satisfied.

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

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

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Amount of increase (decrease) in assets associated with contracts with customers where performance precedes contractual due date.

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Amount of increase in current contract liabilities based on timing of payments received from customers.

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Amount of increase in non-current contract liabilities based on timing of payments received from customers.

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