Revenue Recognition (Contract Assets and Liabilities) (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2018	Oct. 01, 2018
Contract Assets and Liabilities
Contract assets - current	$ 51.5	$ 53.0
Contract fulfillment costs - current	54.0	50.7
Contract liabilities - current	152.4	174.5
Contract liabilities - noncurrent	52.5	$ 53.5
Revenue recognized that was previously included in current contract liabilities	$ 50.0

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

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- References

No definition available.

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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, classified as current.

+ References

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- Definition

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 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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