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Stock-Based Compensation - Summary of Restricted Stock Granted (Details) - Restricted Stock - shares | 9 Months Ended
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Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2017
2010 Plan | 2017 | Five Years |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Vesting Term (In Years) |  |  |  |  | 5 years
Shares | 5,774 |  |  |  |
Remaining Term (In Years) |  |  |  |  | 3 months 18 days
2010 Plan | 2018 | Five Years |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Vesting Term (In Years) |  |  |  | 5 years |
Shares | 6,184 |  |  |  |
Remaining Term (In Years) |  |  |  | 1 year 3 months 18 days |
2010 Plan | 2018 | Four Years |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Vesting Term (In Years) |  |  |  | 4 years |
Shares | 706 |  |  |  |
Remaining Term (In Years) |  |  |  | 3 months 18 days |
2010 Plan | 2019 | Three Years |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Vesting Term (In Years) |  |  | 3 years |  |
Shares | 16,254 |  |  |  |
Remaining Term (In Years) |  |  | 3 months 18 days |  |
2020 Plan | 2020 | Three Years |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Vesting Term (In Years) |  | 3 years |  |  |
Shares | 20,342 |  |  |  |
Remaining Term (In Years) |  | 1 year 3 months 18 days |  |  |
2020 Plan | 2020 | Two Years |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Vesting Term (In Years) |  | 2 years |  |  |
Shares | 694 |  |  |  |
Remaining Term (In Years) |  | 3 months 18 days |  |  |
2010 and 2020 Equity Incentive Plan |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Shares | 81,240 |  |  |  |
Remaining Term (In Years) | 1 year 3 months 18 days |  |  |  |
2010 and 2020 Equity Incentive Plan | 2021 | Three Years |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Vesting Term (In Years) | 3 years |  |  |  |
Shares | 27,172 |  |  |  |
Remaining Term (In Years) | 2 years 3 months 18 days |  |  |  |
2010 and 2020 Equity Incentive Plan | 2021 | One Year |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Vesting Term (In Years) | 1 year |  |  |  |
Shares | 4,114 |  |  |  |
Remaining Term (In Years) | 3 months 18 days |  |  |  |

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- Definition Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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