XML 68 R54.htm IDEA: XBRL DOCUMENT
v3.21.1

Employee Benefit Plan - Additional Information (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Compensation And Retirement Disclosure [Abstract] |  |
Employer matching contribution, percentage | 50.00% |
Employer matching contribution of employees' contribution, percentage | 6.00% |
Employer matching contribution amount | $ 119,000 | $ 115,000
Annual vesting percentage of employer contributions | 20.00% |
Vesting period of employer matching contributions | 6 years |
Vesting percentage of employer contributions by year six | 100.00% |

X
- Definition Vesting period of employer's matching contributions to a defined contribution plan. + References No definition available. + Details
Name: | lgl_DefinedContributionPlanEmployersMatchingContributionVestingPeriod
Namespace Prefix: | lgl_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition The vesting percentage of employer contributions by the sixth year of participating in the defined contribution plan. + References No definition available. + Details
Name: | lgl_VestingPercentageOfEmployerContributionsByYearSix
Namespace Prefix: | lgl_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_CompensationAndRetirementDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of discretionary contributions made by an employer to a defined contribution plan. + References No definition available. + Details
Name: | us-gaap_DefinedContributionPlanEmployerDiscretionaryContributionAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan. + References No definition available. + Details
Name: | us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of employer's matching contributions to a defined contribution plan that vests in a given year. + References No definition available. + Details
Name: | us-gaap_DefinedContributionPlanEmployersMatchingContributionAnnualVestingPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan. + References No definition available. + Details
Name: | us-gaap_DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration