Investments - Summary of Amortized Cost and Estimated Fair Value of Available-for-Sale Investments, Excluding VIE Investments (Detail) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Debt Securities, Available-for-sale [Line Items]
Fixed income securities, amortized cost	$ 269,848	$ 289,712
Gross Unrealized Gains	1,205	260
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments	2,316	5,351
Available-for-sale Securities	122,295	157,020
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-Sale, Current	268,737	284,621
Municipal Bonds [Member]
Debt Securities, Available-for-sale [Line Items]
Fixed income securities, amortized cost	11,697	14,646
Gross Unrealized Gains	121	7
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments	228	570
Available-for-sale Securities	11,590	14,083
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Corporate Obligations [Member]
Debt Securities, Available-for-sale [Line Items]
Fixed income securities, amortized cost	67,881	92,990
Gross Unrealized Gains	634	107
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments	1,942	3,905
Available-for-sale Securities	66,573	89,192
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
U.S. Government Obligations [Member]
Debt Securities, Available-for-sale [Line Items]
Fixed income securities, amortized cost	35,190	41,706
Gross Unrealized Gains	365	98
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments	131	809
Available-for-sale Securities	35,424	40,995
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Residential Mortgage-Backed Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Fixed income securities, amortized cost	1,604	2,475
Gross Unrealized Gains	0	0
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments	7	29
Available-for-sale Securities	1,597	2,446
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Collateralized Debt Obligations [Member]
Debt Securities, Available-for-sale [Line Items]
Fixed income securities, amortized cost	1,963	3,131
Gross Unrealized Gains	12	13
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments	0	2
Available-for-sale Securities	1,975	3,142
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Asset-backed Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Fixed income securities, amortized cost	1,772	5,049
Gross Unrealized Gains	23	14
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments	0	2
Available-for-sale Securities	1,795	5,061
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Short-term Investments [Member]
Debt Securities, Available-for-sale [Line Items]
Fixed income securities, amortized cost	146,434	127,588
Gross Unrealized Gains	8	13
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments	0	0
Available-for-sale Securities	146,442	127,601
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Commercial Mortgage Backed Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Fixed income securities, amortized cost	3,307
Gross Unrealized Gains	42	8
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments	8	34
Available-for-sale Securities	3,341	2,101
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Collateralized Mortgage Backed Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Fixed income securities, amortized cost	3,307	2,127
Long-Term Investments
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains	1,197	247
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments	2,316	5,351
Available-for-sale Securities	122,295	157,020
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Long-Term Investments \| Fixed Income Investments And Other Investments [Member]
Debt Securities, Available-for-sale [Line Items]
Fixed income securities, amortized cost	$ 123,414	$ 162,124

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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