v3.25.2
Financial Instruments and Fair Value Measurements - Carrying Amount and Fair Value (Details) - Nonrecurring - USD ($)
$ in Thousands
Jun. 30, 2025
Dec. 31, 2024
Carrying Value    
Financial instruments and fair value measurements    
Debt $ 432,421 $ 442,716
Fair Value    
Financial instruments and fair value measurements    
Debt 384,658 391,356
Level 1 | Carrying Value | U.S. Treasury Bills    
Financial instruments and fair value measurements    
Investments held by SPEs 2,774 3,143
Level 1 | Fair Value | U.S. Treasury Bills    
Financial instruments and fair value measurements    
Investments held by SPEs 2,750 3,078
Level 2 | Carrying Value | Fixed-rate debt    
Financial instruments and fair value measurements    
Debt 282,451 258,135
Level 2 | Carrying Value | Variable rate debt    
Financial instruments and fair value measurements    
Debt 149,970 184,581
Level 2 | Fair Value | Fixed-rate debt    
Financial instruments and fair value measurements    
Debt 234,688 206,775
Level 2 | Fair Value | Variable rate debt    
Financial instruments and fair value measurements    
Debt 149,970 184,581
Level 3 | Carrying Value    
Financial instruments and fair value measurements    
Senior Notes held by SPE 178,650 178,484
Level 3 | Carrying Value | Time deposit    
Financial instruments and fair value measurements    
Investments held by SPEs 200,000 200,000
Level 3 | Fair Value    
Financial instruments and fair value measurements    
Senior Notes held by SPE 182,875 178,473
Level 3 | Fair Value | Time deposit    
Financial instruments and fair value measurements    
Investments held by SPEs $ 200,000 $ 200,000