Note 9 - Share-based Compensation and Employee Benefit Plan (Details Textual) - USD ($)	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Labor and Related Expense	$ 2,216,000	$ 3,861,000
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay	50.00%
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent	6.00%
Defined Contribution Plan, Cost	$ 48,000	89,000
Restricted Stock [Member]
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount	$ 149,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)	1 year 259 days
2012 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)	3,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)	2,850,507
Share-based Payment Arrangement, Expense	$ 34,000	43,000
2012 Stock Plan [Member] \| Employee [Member]
Share-based Payment Arrangement, Expense	15,000	25,000
2012 Stock Plan [Member] \| Patriot's External Directors [Member]
Share-based Payment Arrangement, Expense	19,000	18,000
Labor and Related Expense	$ 94,000	$ 117,000
2012 Stock Plan [Member] \| Restricted Stock [Member] \| Share-based Payment Arrangement, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	4 years
2012 Stock Plan [Member] \| Restricted Stock [Member] \| Share-based Payment Arrangement, Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	5 years
2012 Stock Plan [Member] \| Restricted Stock [Member] \| Share-based Payment Arrangement, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	3 years

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of cost for defined contribution plan.

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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Amount of expense for salary, wage, profit sharing; incentive and equity-based compensation; and other employee benefit.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Number of shares authorized for issuance under share-based payment arrangement.

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