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Restricted Shares Issued in Conjunction with Stock Plan (Detail) - Restricted Stock $ in Millions | 12 Months Ended
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Dec. 31, 2022 USD ($) shares
Period 1 |
Class of Stock [Line Items] |
Issuance Date | Jan. 28, 2020
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period | shares | 28,630
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Aggregate Intrinsic Value | $ | $ 1.8
Period 2 |
Class of Stock [Line Items] |
Issuance Date | Jul. 28, 2020
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period | shares | 3,000
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Aggregate Intrinsic Value | $ | $ 0.1
Period 3 |
Class of Stock [Line Items] |
Issuance Date | Jan. 26, 2021
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period | shares | 23,140
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Aggregate Intrinsic Value | $ | $ 0.9
Period 4 |
Class of Stock [Line Items] |
Issuance Date | Jan. 25, 2022
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period | shares | 36,770
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Aggregate Intrinsic Value | $ | $ 1.7

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