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Employee Benefit Plans - Additional Information (Detail) - 401 K Plan [Member] - USD ($) | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Defined Contribution Plan Disclosure [Line Items] |  |  |
Minimum percentage of total annual compensation allowed to be deferred | 1.00% |  |
Employer matching contribution, description | Once eligible full-time employees have completed a minimum of one (1) year of service, and part time employees have worked at least 500 hours, the Company matches employee contributions to the 401(k) Plan in an amount per employee equal to one-third of the first 6% of the employee’s annual contributions, subject to legal limits. |  |
Employee contributions to 401(k) Plan matched by company in an amount per employee of first 6% of employee's annual contributions | 33.33% |  |
Defined benefit plan amount expense | $ 203,000 | $ 193,000 | $ 182,000

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- Definition Amount of cost for defined contribution plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942 + Details
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- Definition Percentage employer matches of the employee's percentage contribution matched. + References No definition available. + Details
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- Details
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