Sales - Contract liabilities (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 29, 2019	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Deferred revenue - current	$ 306.2	$ 288.1
Deferred revenue - noncurrent	97.3	92.6
Total contract liabilities	403.5	$ 380.7
Contract liabilities, revenue recognized	$ 114.3

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
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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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- References

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