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Note 11 - Retirement Plans (Details Textual) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2021 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
Retirement Plan Expense |  | $ 1,800,000 | $ 1,600,000 | $ 1,200,000
Defined Contribution Plan [Member] |  |  |  |
Company Matching Percentage on First Eight Percent of Employee Contributions |  | 50.00% | 50.00% | 50.00%
Employee Contribution Percentage for Which Company Will Match at Fifty Percent |  | 8.00% | 8.00% | 6.00%
ParkUSA Defined Contribution Plan [Member] |  |  |  |
Company Matching Percentage on First Eight Percent of Employee Contributions | 100.00% |  |  |
Employee Contribution Percentage for Which Company Will Match at One Hundred Percent | 4.00% |  |  |
Pension Plan [Member] |  |  |  |
Number of Non-contributory Defined Benefit Plans |  | 2 |  |
Liability, Defined Benefit Plan, Total | $ 1,000,000.0 | $ 1,000,000.0 | $ 1,600,000 |
Accumulated Other Comprehensive Income (Loss), Unrecognized Net Actuarial Losses, Net of Tax | 1,500,000 | 1,500,000 | 1,800,000 |
Defined Benefit Plan, Accumulated Benefit Obligation | 6,100,000 | 6,100,000 | 6,500,000 |
Defined Benefit Plan, Plan Assets, Amount, Ending Balance | $ 5,100,000 | 5,100,000 | 4,900,000 |
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Total |  | $ 0 | $ 0 | $ 0
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate | 2.41% | 2.41% | 2.04% |
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets |  | 7.00% | 7.00% |
Non-qualified Retirement Savings Plan [Member] |  |  |  |
Company Matching Percentage on First Ten Thousand Dollar Employee Contributions |  | 50.00% |  |
Officer Contribution for Which Company Will Match at Fifty Percent |  | $ 10,000 |  |
Select Employee Contribution for Which Company Will Match at Fifty Percent |  | 5,000 |  |
Non-qualified Retirement Savings Plan [Member] | Other Long-term Liabilities [Member] |  |  |  |
Deferred Compensation Liability, Classified, Noncurrent, Total | $ 4,300,000 | $ 4,300,000 | $ 4,700,000 |

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