Stock Transactions And Stock-Based Compensation - Narrative (Details) $ / shares in Units, $ in Millions		12 Months Ended
	Jan. 21, 2022 USD ($) shares	Dec. 31, 2025 USD ($) vote $ / shares shares	Dec. 31, 2024 USD ($) $ / shares shares	Dec. 31, 2023 USD ($) shares	Feb. 05, 2025 USD ($)	Dec. 31, 2022 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares authorized (in shares)		500,000,000.0	500,000,000.0
Share repurchase program, authorized, amount | $					$ 250.0
Preferred shares authorized (in shares)		15,000,000.0	15,000,000.0
Preferred shares outstanding (in shares)		0	0
Preferred shares issued (in shares)		0	0
Common stock voting rights (in votes per share) | vote		1
Common stock, par value (in USD per share) | $ / shares		$ 0.01	$ 0.01
Stock repurchased during period, value | $		$ 165.9
Stock repurchased during period (in shares)		9,200,000
Total unrecognized compensation cost related to RSUs/PSUs | $		$ 40.8
Granted (in shares)		1,400,000	2,200,000	1,000,000.0
Vested (in period)		900,000	700,000	600,000
Unvested (in shares)		3,200,000	2,900,000	1,700,000		1,500,000
Expected forfeiture rate		12.00%	12.00%	12.00%
Period of recognition		1 year
Aggregate intrinsic value of options exercised | $		$ 1.2	$ 0.8	$ 9.0
Employee service share-based compensation, tax benefit from exercise of stock options | $		$ 2.5	$ 1.6	3.6
Share withheld (in shares)		292,600	242,000
Tax withholding payment related to net settlement of equity awards | $		$ 6.2	$ 5.3	$ 7.9
RSUs | Pacific Dental Services
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period		4 years
Total unrecognized compensation cost related to RSUs/PSUs | $	$ 12.5
Granted (in shares)	273,522
Vested (in period)		182,348
Unvested (in shares)		91,174
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yield		0.00%	0.00%	0.00%
Employee service share-based compensation, tax benefit from exercise of stock options | $		$ 0.1	$ 0.1	$ 1.3
Restricted Stock Units And Performance-Based Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee service share-based compensation, tax benefit from exercise of stock options | $		$ 0.0	$ 0.0	$ 0.2
2019 Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized under the Stock Plan (in shares)		27,100,000
Award expiration period		10 years
2019 Omnibus Incentive Plan | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period		3 years
2019 Omnibus Incentive Plan | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period		5 years