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Stock-Based Compensation (Restricted Stock Units) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Jan. 03, 2023
Share-Based Payment Arrangement, Additional Disclosure
Stock-based compensation	$ 39.7	$ 31.5	$ 35.0
Tax benefits related to vesting of RSUs and exercise of stock options	$ 9.0	$ 9.7	$ 17.2
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Nonvested, shares, beginning balance	1,200,000
Nonvested, weighted-average grant date fair value, beginning balance (in dollars per share)	$ 75.14
Granted, shares	400,000
Granted, weighted-average grant date fair value (in dollars per share)	$ 139.11	$ 112.66	$ 85.45
Vested, shares	(500,000)
Vested, weighted-average grant date fair value (in dollars per share)	$ 60.40
Forfeited, shares	(100,000)
Forfeited, weighted-average grant date fair value (in dollars per share)	$ 112.36
Nonvested, shares, ending balance	1,000,000.0	1,200,000
Nonvested, weighted-average grant date fair value, ending balance (in dollars per share)	$ 108.26	$ 75.14
Share-Based Payment Arrangement, Additional Disclosure
Total fair value of RSU's vested	$ 76.0	$ 85.7	$ 51.8
Stock-based compensation	39.7	31.5	35.0
Tax benefit related to stock-based compensation expense	4.5	$ 4.0	$ 2.4
Unrecognized compensation cost related to non-vested stock-based compensation arrangements	$ 37.4
Unrecognized compensation cost expected to be recognized over weighted average period (in years)	1 year 6 months 3 days
Director [Member] | Restricted Stock Units (RSUs) [Member] | Non-Employee Director Equity Plan 2014 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock units granted to each non-employee director (in shares)				2,331
Employee [Member] | Restricted Stock Units (RSUs) [Member] | Employee Equity and Incentive Plan 2017 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Granted, shares	400,000
Employee [Member] | Time-based Restricted Stock Units [Member] | Employee Equity and Incentive Plan 2017 [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	3 years
Employee [Member] | Time-based Restricted Stock Units [Member] | Employee Equity and Incentive Plan 2017 [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	4 years
Employee [Member] | Performance-based RSUs [Member] | Employee Equity and Incentive Plan 2017 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	3 years
Measurement Period (in years)	3 years
Employee [Member] | Market-based RSUs [Member] | Employee Equity and Incentive Plan 2017 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	3 years
Measurement Period (in years)	3 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Monte Carlo Simulation, Risk Free Interest Rate	4.60%
Monte Carlo Simulation, Expected Volatility Rate	42.89%
Monte Carlo Simulation, Expected Dividend Rate	0.00%

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