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Employee Benefit Plans - Additional Information (Detail) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Defined Contribution Plan Disclosure [Line Items] |  |  |
Minimum percentage of employee contribution to defined contribution plan | 1.00% |  |
Amount of employee contribution to defined contribution plan | $ 19,500 | $ 19,000 |
Employer matching contributions to defined contribution plan | 0 | 0 |
Employee Age Fifty and Above [Member] |  |  |
Defined Contribution Plan Disclosure [Line Items] |  |  |
Amount of employee contribution to defined contribution plan | 26,000 | 25,000 |
Supplemental Employee Retirement Plan [Member] |  |  |
Defined Contribution Plan Disclosure [Line Items] |  |  |
Benefit obligations in excess of the fair value of plan assets | $ 10,805,326 | 9,723,866 | $ 9,038,825
Defined benefit plan, assumption used to calculate discount rate description | The discount rate is based on matching the projected cash flows of the plan to the Citigroup Pension Discount Curve. |  |
Contributions to the plan | $ 544,261 | 367,989 |
Other Noncurrent Liabilities [Member] | Supplemental Employee Retirement Plan [Member] |  |  |
Defined Contribution Plan Disclosure [Line Items] |  |  |
Benefit obligations in excess of the fair value of plan assets |  | $ 10,800,000 | $ 9,700,000

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- Definition Minimum percentage of employee gross pay the employee may contribute to a defined contribution plan. + References No definition available. + Details
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- Definition Description of assumption used to determine benefit obligation and net periodic benefit cost of defined benefit plan. Includes, but is not limited to, discount rate, rate of compensation increase, expected long-term rate of return on plan assets and interest crediting rate. + References No definition available. + Details
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- Definition Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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- Definition Amount of contribution received by defined benefit plan from employer which increases plan assets. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e2709-114920 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 Reference 5: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4587-114921 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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- Definition Maximum amount the employee may contribute to a defined contribution plan. + References No definition available. + Details
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