v3.26.1
Fair Value Measurement and Disclosures - Additional Information (Details) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Dec. 31, 2025
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]          
Investments at fair value $ 1,937,932   $ 1,937,932   $ 1,577,705
Transfers into Level III       $ 0  
Fair Value, Asset (Liability), Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Debt and Equity Securities, Unrealized Gain (Loss) Debt and Equity Securities, Unrealized Gain (Loss) Debt and Equity Securities, Unrealized Gain (Loss) Debt and Equity Securities, Unrealized Gain (Loss)  
Unrealized gain (loss) on investments $ (12,921) $ 2,507 $ (10,653) $ 2,317  
Series I          
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]          
Investments at fair value $ 311,354   311,354   305,789
Transfers out of Level III     $ (327) $ (27)  
Fair Value, Asset (Liability), Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Debt and Equity Securities, Unrealized Gain (Loss) Debt and Equity Securities, Unrealized Gain (Loss) Debt and Equity Securities, Unrealized Gain (Loss) Debt and Equity Securities, Unrealized Gain (Loss)  
Unrealized gain (loss) on investments $ (4,110) $ (1,217) $ (2,297) $ (1,122)  
Series II          
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]          
Investments at fair value $ 1,626,578   1,626,578   1,271,916
Transfers out of Level III     $ (1,352) $ (67)  
Fair Value, Asset (Liability), Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Debt and Equity Securities, Unrealized Gain (Loss) Debt and Equity Securities, Unrealized Gain (Loss) Debt and Equity Securities, Unrealized Gain (Loss) Debt and Equity Securities, Unrealized Gain (Loss)  
Unrealized gain (loss) on investments $ (8,811) $ 3,724 $ (8,356) $ 3,439  
Level I | Money Market Funds          
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]          
Cash and cash equivalents 5,192   5,192   3,502
Level I | Series I          
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]          
Cash and cash equivalents 834   834   640
Level I | Series II          
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]          
Cash and cash equivalents 4,358   4,358   2,862
Level III          
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]          
Investments at fair value 1,429,054   1,429,054   1,023,351
Transfers into Level III 0 0 0 0  
Transfers out of Level III 0 0 (1,679) (94)  
Unrealized gain (loss) on investments (12,921) 2,507 (10,653) 2,317  
Level III | Series I          
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]          
Investments at fair value 229,596   229,596   198,345
Transfers into Level III 0 0 0 0  
Transfers out of Level III 0 0 (327) (27)  
Unrealized gain (loss) on investments (4,110) (1,217) (2,297) (1,122)  
Level III | Series II          
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]          
Investments at fair value 1,199,458   1,199,458   $ 825,006
Transfers into Level III 0 0 0 0  
Transfers out of Level III 0 0 (1,352) (67)  
Unrealized gain (loss) on investments $ (8,811) $ 3,724 $ (8,356) $ 3,439