Revenue Recognition - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2019	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Total contract assets	$ 13.7	$ 13.7	$ 12.1
Total advances on contracts	47.2	47.2	$ 67.1
Revenue recognized	$ 17.0	53.0
Contract with Customer, Performance Obligation Satisfied in Previous Period		$ 0.8

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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- 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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- 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

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- Definition

Amount of revenue recognized from performance obligation satisfied or partially satisfied in previous reporting periods. Includes, but is not limited to, change in transaction price.

+ References

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