Fair Value - Valuation Techniques (Details) $ in Thousands	Sep. 30, 2026 USD ($)	Jun. 30, 2026 USD ($)	Dec. 31, 2025 USD ($)	Sep. 30, 2025 USD ($)	Jun. 30, 2025 USD ($)	Dec. 31, 2024 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Limited partnership interests	$ 99,920	$ 84,682	$ 65,335	$ 45,141	$ 39,247	$ 32,552
Limited partnership interests \| Discounted cash flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Limited partnership interests	87,321		$ 65,335
Limited partnership interests \| Valuation, Cost Approach
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Limited partnership interests	$ 12,599
Level 3 \| Discount Rate \| Discounted cash flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Weighted average measurement input	0.0862		0.0882
Level 3 \| Discount Rate \| Discounted cash flow \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.0675		0.0700
Level 3 \| Discount Rate \| Discounted cash flow \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.0950		0.1000
Level 3 \| Terminal Capitalization Rate \| Discounted cash flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Weighted average measurement input	0.0723		0.0740
Level 3 \| Terminal Capitalization Rate \| Discounted cash flow \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.0525		0.0525
Level 3 \| Terminal Capitalization Rate \| Discounted cash flow \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.0800		0.0875