Summary of Estimated Fair Values of Bonds Held on Deposit (Parenthetical) (Detail) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Schedule Of Available For Sale Securities [Line Items]
Cash and cash equivalents	$ 35,737	$ 38,846
Remainder Related to Bonds Available for Sale
Schedule Of Available For Sale Securities [Line Items]
Cash and cash equivalents	$ 4,100	$ 3,700

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/exampleRef
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