Segment and Geographic Information - Identifiable Assets (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Identifiable assets	$ 1,954.7	$ 1,898.4
United States
Segment Reporting Information [Line Items]
Identifiable assets	1,781.0	1,741.4
Canada
Segment Reporting Information [Line Items]
Identifiable assets	$ 173.7	$ 157.0

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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+ Details