Business Combinations (Schedule of Purchase Price Allocation) (Details) - USD ($) $ in Millions	Mar. 20, 2023	Jan. 22, 2023	Jan. 03, 2023	Jun. 30, 2024	Dec. 31, 2023
Liabilities assumed
Goodwill acquired on acquisition				$ 4,526.4	$ 4,537.0
IAA acquisition
Business Acquisition [Line Items]
Cash consideration	$ 1,714.2	$ 1,700.0
Fair value of common shares issued	3,712.9
Repayment of IAA net debt	1,157.1
Reimbursement of sell-side acquisition costs	48.8
Fair value of exchanged IAA equity awards attributable to pre-combination service	13.1
Purchase price	6,646.1
Assets acquired
Cash and cash equivalents	166.6
Trade and other receivables	497.3
Inventory	57.1
Other current assets	28.0
Income taxes receivable	0.6
Property, plant and equipment	618.5
Operating lease right-of-use assets	1,289.7
Other non-current assets	34.8
Intangible assets	2,712.1
Liabilities assumed
Auction proceeds payable	60.7
Trade and other liabilities	257.0
Current operating lease liability	77.5
Income taxes payable	3.5
Long-term operating lease liability	1,192.7
Other non-current liabilities	24.3
Deferred tax liabilities	689.5
Fair value of identifiable net assets acquired	3,099.5
Goodwill acquired on acquisition	$ 3,546.6
VeriTread
Business Acquisition [Line Items]
Cash consideration			$ 28.1
Fair value of previously held equity interest			4.3
Purchase price			32.4
Assets acquired
Cash and cash equivalents			3.4
Trade and other receivables			0.9
Intangible assets			14.7
Liabilities assumed
Trade and other liabilities			1.1
Fair value of identifiable net assets acquired			17.9
Redeemable non-controlling interest			(8.9)
Non-controlling interest			(1.8)
Goodwill acquired on acquisition			$ 25.2