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Retirement Plans - Additional Information (Detail) - USD ($) | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Defined Contribution Plan Disclosure [Line Items] |  |  |
Defined contribution plan, new plan effective date | 2014-01 |  |
Contribution Plan [Member] |  |  |
Defined Contribution Plan Disclosure [Line Items] |  |  |
Defined contribution plan minimum eligible period | have completed one month of service. |  |
Defined contribution plan, maximum percentage of employee contribution | 100.00% |  |
Defined contribution plan, percentage of employer matching contribution percent of match | 50.00% |  |
Defined contribution plan, employer contribution percentage | 8.00% |  |
Defined contribution plan, maximum annual employer contribution per employee | $ 4,000 |  |
Defined contribution plan, matching employer contributions | $ 1,100,000 | $ 920,000 | $ 733,000
Contribution Plan [Member] | One Year of Service [Member] |  |  |
Defined Contribution Plan Disclosure [Line Items] |  |  |
Defined contribution plan, vesting percentage per year | 33.00% |  |
Contribution Plan [Member] | Two Year of Service [Member] |  |  |
Defined Contribution Plan Disclosure [Line Items] |  |  |
Defined contribution plan, vesting percentage per year | 66.00% |  |
Contribution Plan [Member] | Three Year of Service [Member] |  |  |
Defined Contribution Plan Disclosure [Line Items] |  |  |
Defined contribution plan, vesting percentage per year | 100.00% |  |

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- Definition Maximum amount contributed by the employer, with respect to a matched employee contribution, to a defined contribution plan annually. + References No definition available. + Details
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- Definition Description of the deferred compensation arrangement, including fixed amounts and determinable awards, or the method for determining payments and awards, the timing of such payments and awards, and any requisite service or performance criteria, as of the balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 710 -SubTopic 10 -Section 55 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6409961&loc=d3e20487-108367 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5047-113901 + Details
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- Definition Amount of cost for defined contribution plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -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 Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan. + References No definition available. + 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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- Definition Percentage of employer's matching contributions to a defined contribution plan that vests in a given year. + References No definition available. + Details
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- Definition Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan. + References No definition available. + Details
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