Supplemental Cash Flow Information - Reconciliation of Cash, Cash Equivalents, and Restricted Cash (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Supplemental Cash Flow Elements [Abstract]
Cash and cash equivalents	$ 813.2	$ 895.3	$ 405.6	$ 382.3
Restricted cash recorded in Prepaid expenses and other current assets	59.1	70.1	62.3	42.5
Total cash, cash equivalents and restricted cash in the statements of cash flows	$ 872.3	$ 965.4	$ 467.9	$ 424.8