Investments - Additional Information (Detail)	3 Months Ended
Mar. 31, 2026 USD ($) Entity ParntershipInvestments	Dec. 31, 2025 USD ($)
Schedule Of Available For Sale Securities [Line Items]
Investments in a single issuer as a percentage of shareholders' equity	2.70%	2.70%
Number of limited partnership investments \| ParntershipInvestments	3
Fixed maturity securities with market value	$ 0	$ 0
Future Funding Commitments	11,214,000	11,214,000
Limited partnership investments with carrying value of fair value	$ 10,200,000	17,100,000
Variable Interest Entity, Not Primary Beneficiary
Schedule Of Available For Sale Securities [Line Items]
Number of VIE's \| Entity	2
Ownership interest exceeds respective investments	3.00%
One of the Company's variable interest VIE's, invests in distressed securities and assets
Schedule Of Available For Sale Securities [Line Items]
Significant variable interest in carrying value of the non-consolidated VIE	$ 1,600,000	1,700,000
Future Funding Commitments	11,200,000
Variable interest entities, maximum exposure to loss		12,900,000
Second VIE that invests in REIT qualifying assets
Schedule Of Available For Sale Securities [Line Items]
Significant variable interest in carrying value of the non-consolidated VIE	6,100,000	6,000,000
Variable interest entities, maximum exposure to loss	6,100,000	6,000,000
Other Assets
Schedule Of Available For Sale Securities [Line Items]
Accrued interest receivable related to fixed maturities	4,000,000	$ 4,800,000
U.S. Treasuries
Schedule Of Available For Sale Securities [Line Items]
Gross unrealized losses	165,000
Obligations of States and Political Subdivisions
Schedule Of Available For Sale Securities [Line Items]
Gross unrealized losses	384,000
Mortgage Backed Securities
Schedule Of Available For Sale Securities [Line Items]
Gross unrealized losses	3,510,000
Asset-backed Securities
Schedule Of Available For Sale Securities [Line Items]
Gross unrealized losses	$ 3,828,000
Weighted average credit enhancement	34.60%
Commercial Mortgage-Backed Securities
Schedule Of Available For Sale Securities [Line Items]
Gross unrealized losses	$ 1,457,000
Weighted average credit enhancement	40.80%
Corporate Bonds
Schedule Of Available For Sale Securities [Line Items]
Gross unrealized losses	$ 980,000
Foreign Corporate Bonds
Schedule Of Available For Sale Securities [Line Items]
Gross unrealized losses	$ 736,000

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