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v3.23.1

Selected Balance Sheet Data - Narrative (Detail) - USD ($) $ in Thousands |  |  |  | 3 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Jan. 01, 2022 | Jan. 01, 2021 | Jan. 01, 2014 | Mar. 31, 2023 | Mar. 31, 2022 | Dec. 31, 2022 | Mar. 31, 2013
Schedule Of Accrued Expenses [Line Items] |  |  |  |  |  |  |
Advances and loans and commissions receivable allowance for credit loss |  |  |  | $ 848 |  | $ 791 |
SARs frozen liability amount |  |  |  | $ 10,847 |  | $ 13,137 |
Treasury note term |  |  |  | 1 year |  |  |
Interest expense |  |  |  | $ 215 | $ 160 |  |
Commissions Payable |  |  |  |  |  |  |
Schedule Of Accrued Expenses [Line Items] |  |  |  |  |  |  |
Maximum payment deferral period for certain commissions payable |  |  |  | 3 years |  |  |
SARs |  |  |  |  |  |  |
Schedule Of Accrued Expenses [Line Items] |  |  |  |  |  |  |
SARs frozen liability amount |  |  |  |  |  |  | $ 20,000
Treasury note term |  |  | 10 years |  |  |  |
Base spread on SARs liability variable rate |  |  | 2.00% |  |  |  |
SARs liability interest accrual rates | 3.63% | 5.79% |  |  |  |  |
Interest expense |  |  |  | $ 190 | 135 |  |
Payments for SARs Liability |  |  |  | $ 2,200 | 2,300 |  |
Deferred Compensation Liability |  |  |  |  |  |  |
Schedule Of Accrued Expenses [Line Items] |  |  |  |  |  |  |
Fair value of deferred compensation plan assets |  |  |  | 110.00% |  |  |
Payments made during the period |  |  |  | $ 48 | $ 365 |  |
Deferred Compensation Liability | Minimum |  |  |  |  |  |  |
Schedule Of Accrued Expenses [Line Items] |  |  |  |  |  |  |
Payout period |  |  |  | 2 years |  |  |
Deferred Compensation Liability | Maximum |  |  |  |  |  |  |
Schedule Of Accrued Expenses [Line Items] |  |  |  |  |  |  |
Payout period |  |  |  | 15 years |  |  |

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