v3.26.1
Realized and Net Change in Unrealized Gains (Losses) on Financial Instruments on Financial Instruments on Which Fair Value Option was Elected (Detail) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Realized Gains (Losses) | Debt Securities    
Fair Value, Option, Quantitative Disclosures [Line Items]    
Realized and net change in unrealized gains (losses) on financial instruments $ (11,226) $ 642
Realized Gains (Losses) | Assets    
Fair Value, Option, Quantitative Disclosures [Line Items]    
Realized and net change in unrealized gains (losses) on financial instruments (9,931) (9,790)
Realized Gains (Losses) | Loans and Receivables    
Fair Value, Option, Quantitative Disclosures [Line Items]    
Realized and net change in unrealized gains (losses) on financial instruments (32) (656)
Realized Gains (Losses) | Equity and Preferred Securities    
Fair Value, Option, Quantitative Disclosures [Line Items]    
Realized and net change in unrealized gains (losses) on financial instruments 1,327 (8,064)
Realized Gains (Losses) | Corporate Loans    
Fair Value, Option, Quantitative Disclosures [Line Items]    
Realized and net change in unrealized gains (losses) on financial instruments   (1,712)
Net Change In Unrealized Gains (Losses) | Debt Securities    
Fair Value, Option, Quantitative Disclosures [Line Items]    
Realized and net change in unrealized gains (losses) on financial instruments 8,555 (1,014)
Net Change In Unrealized Gains (Losses) | Assets    
Fair Value, Option, Quantitative Disclosures [Line Items]    
Realized and net change in unrealized gains (losses) on financial instruments 30,364 25,112
Net Change In Unrealized Gains (Losses) | Loans and Receivables    
Fair Value, Option, Quantitative Disclosures [Line Items]    
Realized and net change in unrealized gains (losses) on financial instruments (1,153) (24)
Net Change In Unrealized Gains (Losses) | Liabilities    
Fair Value, Option, Quantitative Disclosures [Line Items]    
Realized and net change in unrealized gains (losses) on financial instruments (1,857) 423
Net Change In Unrealized Gains (Losses) | Equity and Preferred Securities    
Fair Value, Option, Quantitative Disclosures [Line Items]    
Realized and net change in unrealized gains (losses) on financial instruments 22,962 25,112
Net Change In Unrealized Gains (Losses) | Corporate Loans    
Fair Value, Option, Quantitative Disclosures [Line Items]    
Realized and net change in unrealized gains (losses) on financial instruments   1,038
Net Change In Unrealized Gains (Losses) | CLO Notes Payable    
Fair Value, Option, Quantitative Disclosures [Line Items]    
Realized and net change in unrealized gains (losses) on financial instruments   859
Net Change In Unrealized Gains (Losses) | Corporate Treasury Commitments    
Fair Value, Option, Quantitative Disclosures [Line Items]    
Realized and net change in unrealized gains (losses) on financial instruments $ (1,857) $ (436)