Revenue (Summary of Contract Assets) (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Revenue from Contract with Customer [Abstract]
Accounts receivable, less allowance for credit losses	$ 184.7	$ 188.5
Deferred commissions, current and non-current	30.7	30.4
Total contract assets	$ 215.4	$ 218.9

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
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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