Temporary Equity, Equity and Dividends (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions						1 Months Ended	3 Months Ended
	Mar. 20, 2023	Mar. 15, 2023	Feb. 01, 2023	Jan. 22, 2023	Jan. 03, 2023	May 10, 2023	Mar. 31, 2023	Mar. 31, 2022	Mar. 03, 2023	Dec. 31, 2022
Dividends Payable [Line Items]
Common stock, unlimited shares authorized							Unlimited
Issuance of common stock							$ 15.0
Preferred Stock, preferential dividends							4.3
Preferred Stock dividends paid		$ 3.1
Dividends accrued and unpaid							1.2
Participating dividends accrued and unpaid									$ 1.8
Gain (Loss) from intra-entity foreign currency transactions							$ 1.3	$ (0.9)
Special Dividend [Member]
Dividends Payable [Line Items]
Dividends declared (USD per share)							$ 1.0800
Securities Purchase Agreement [Member]
Dividends Payable [Line Items]
Initial conversion price			$ 73.00
Starboard Value LP and certain of its affiliates | Securities Purchase Agreement [Member]
Dividends Payable [Line Items]
Issuance of common stock			$ 15.0
Shares issued for business combination [Member]
Dividends Payable [Line Items]
Share capital from additional paid-in capital							$ 0.3
Unrecognized share based continuing employment costs							$ 2.4	$ 3.2
Unrecognized share based continuing employment costs, weighted average period for recognition							10 months 24 days
VeriTread
Dividends Payable [Line Items]
Non-controlling interest, percentage					4.00%
Series A Senior Preferred Shares [Member]
Dividends Payable [Line Items]
Temporary equity, authorized shares							485,000,000
Issuance of redeemable convertible preferred stock							$ 482.0
Series A Senior Preferred Shares [Member] | Starboard Value LP and certain of its affiliates | Securities Purchase Agreement [Member]
Dividends Payable [Line Items]
Issuance of redeemable convertible preferred stock			$ 485.0
Initial preferred dividend, percentage			5.50%
Participating dividends			$ 0.27
Increase in preferred dividend rate in fourth anniversary, percentage			7.50%
Spread on variable rate, percentage			6.00%
Increase in preferred dividend rate in ninth anniversary, percentage			10.50%
Notice term for redemption of preferred shares			45 days
Redemption price, percentage			100.00%
Subsequent Event
Dividends Payable [Line Items]
Dividends declared (USD per share)						$ 0.27
Dividends payable date						Jun. 20, 2023
Dividends, date of record						May 30, 2023
IAA, Inc [Member]
Dividends Payable [Line Items]
Cash consideration	$ 1,714.2			$ 1,700.0
VeriTread
Dividends Payable [Line Items]
Prior holdings of issued and outstanding shares, percent					11.00%
Voting equity interests owned including previous interest, percentage					75.00%
Cash consideration					$ 28.1
Remaining units ownership interest, percentage					21.00%