Share-based Payments (Narrative) (Details) - USD ($)			1 Months Ended	3 Months Ended			4 Months Ended	9 Months Ended
	Jun. 15, 2023	Mar. 20, 2023	Aug. 31, 2023	Sep. 30, 2023	Mar. 31, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2023	Sep. 30, 2022	May 09, 2023	May 08, 2023	Dec. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment expense				$ 14,900,000		$ 10,700,000		$ 41,800,000	$ 33,900,000
Maximum contribution				25,000			$ 25,000	$ 25,000
Stock options and ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options assumed in acquisition (in shares)								187,727
Unrecognized compensation costs				5,800,000			5,800,000	$ 5,800,000
Unrecognized compensation costs, period for recognition								2 years 2 months 12 days
Stock options granted (in shares)								262,725
Premium-priced stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options assumed in acquisition (in shares)								0
Unrecognized compensation costs				1,700,000			1,700,000	$ 1,700,000
Unrecognized compensation costs, period for recognition								1 year 1 month 6 days
Weighted average estimated grant date fair value (usd per share)									$ 8.00
Stock options granted (in shares)								0
PSUs with Market Conditions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs				$ 6,100,000			6,100,000	$ 6,100,000
Unrecognized compensation costs, period for recognition								2 years 3 months 18 days
Performance period								3 years
Weighted average grant date fair value of options granted				$ 85.33		$ 69.92
Award holding period						1 year
Discount value						$ 5.34
Effective tax rate						35.00%
Performance Share Units With Market Conditions - June 2022 Grants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period								2 years
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs				$ 20,100,000			20,100,000	$ 20,100,000
Unrecognized compensation costs, period for recognition								1 year 6 months
Deferred Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs				0			0	$ 0
Share unit liability				8,300,000			8,300,000	8,300,000				$ 6,300,000
Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Purchase of shares in company	85.00%
Senior Executive PSU Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs				$ 9,500,000			$ 9,500,000	$ 9,500,000
Unrecognized compensation costs, period for recognition								1 year 10 months 24 days
Performance period			3 years
IAA
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options assumed in acquisition (in shares)		187,727
Number of RSUs assumed in acquisition (in shares)		366,379
Estimated aggregate fair value of converted share-based awards		$ 24,900,000
Share-based payment expense		4,800,000
IAA | Non-employee directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment expense		300,000
IAA | Former executives
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment expense		$ 4,300,000
IAA | Stock options and ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average share price of options assumed (usd per share)								$ 15.52
Performance Share Unit Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Market value of shares vested and released					$ 0			$ 0
Senior Executive PSU Plan | Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)			159,475
2023 Share Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining shares authorized for grant (in shares)											9,355,000
2023 Share Incentive Plan | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)				88,889
2023 ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining shares authorized for grant (in shares)										3,000,000
Share issued under ESPP								0
2023 ESPP | Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Market price discount							15.00%