Investments (Limited Partnership Investments) - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Schedule Of Investments [Line Items]
Net income from limited partnership interests			$ 542	$ 1,799
Distributions received from limited partnership interests			421	2,046
Limited Partnership [Member]
Schedule Of Investments [Line Items]
Net income from limited partnership interests	$ (11)	$ 19	542	1,799
Estimated favorable change in net asset value		516		516
Cash distributions	1,112	2,785	3,017	4,381
Distributions received from limited partnership interests	118	$ 1,235	421	$ 2,046
Company's net cumulative contributed capital to the partnership	22,271		22,271		$ 24,978
Maximum exposure loss relating to VIE	$ 23,115		$ 23,115		$ 25,702