v3.26.1
Fair Value Measurements (Details) - USD ($)
$ in Millions
Jun. 30, 2026
Dec. 31, 2025
Debt Securities, Available-for-sale [Line Items]    
Amortized Cost $ 1,011.1  
Debt Securities, Available-for-sale 1,007.2  
Fair Value, Recurring    
Debt Securities, Available-for-sale [Line Items]    
Debt Securities, Available-for-sale 1,007.2 $ 939.6
Fair Value, Recurring | Corporate Debt Securities [Member]    
Debt Securities, Available-for-sale [Line Items]    
Debt Securities, Available-for-sale 475.7 451.9
Fair Value, Recurring | Municipal obligations [Member]    
Debt Securities, Available-for-sale [Line Items]    
Debt Securities, Available-for-sale 12.8 14.9
Fair Value, Recurring | US Government Sponsored Agencies [Member]    
Debt Securities, Available-for-sale [Line Items]    
Debt Securities, Available-for-sale 120.1 79.6
Fair Value, Recurring | Foreign Government Obligations [Member]    
Debt Securities, Available-for-sale [Line Items]    
Debt Securities, Available-for-sale 9.0 11.7
Fair Value, Recurring | Asset-backed Securities [Member]    
Debt Securities, Available-for-sale [Line Items]    
Debt Securities, Available-for-sale 389.6 381.5
Fair Value, Recurring | Location, Statement of Financial Position, Balance [Axis]: us-gaap:ShortTermInvestments    
Debt Securities, Available-for-sale [Line Items]    
Amortized Cost 1,011.1 931.6
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax 1.9 8.8
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax (5.8) (0.8)
Debt Securities, Available-for-sale 1,007.2 939.6
Fair Value, Recurring | Location, Statement of Financial Position, Balance [Axis]: us-gaap:ShortTermInvestments | Corporate Debt Securities [Member]    
Debt Securities, Available-for-sale [Line Items]    
Amortized Cost 477.5 447.4
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax 1.0 4.6
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax (2.8) (0.1)
Debt Securities, Available-for-sale 475.7 451.9
Fair Value, Recurring | Location, Statement of Financial Position, Balance [Axis]: us-gaap:ShortTermInvestments | Municipal obligations [Member]    
Debt Securities, Available-for-sale [Line Items]    
Amortized Cost 12.8 14.6
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax 0.1 0.3
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax (0.1) 0.0
Debt Securities, Available-for-sale 12.8 14.9
Fair Value, Recurring | Location, Statement of Financial Position, Balance [Axis]: us-gaap:ShortTermInvestments | US Government Sponsored Agencies [Member]    
Debt Securities, Available-for-sale [Line Items]    
Amortized Cost 121.0 79.1
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax 0.0 0.5
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax (0.9) 0.0
Debt Securities, Available-for-sale 120.1 79.6
Fair Value, Recurring | Location, Statement of Financial Position, Balance [Axis]: us-gaap:ShortTermInvestments | Foreign Government Obligations [Member]    
Debt Securities, Available-for-sale [Line Items]    
Amortized Cost 9.0 11.6
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax 0.0 0.1
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax 0.0 0.0
Debt Securities, Available-for-sale 9.0 11.7
Fair Value, Recurring | Location, Statement of Financial Position, Balance [Axis]: us-gaap:ShortTermInvestments | Asset-backed Securities [Member]    
Debt Securities, Available-for-sale [Line Items]    
Amortized Cost 390.8 378.9
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax 0.8 3.3
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax (2.0) (0.7)
Debt Securities, Available-for-sale $ 389.6 $ 381.5