Note 9 - Share-based Compensation and Employee Benefit Plan (Details Textual) - USD ($)	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Labor and Related Expense	$ 3,861,000	$ 3,184,000
Common Stock, Dividends, Per Share, Cash Paid (in dollars per share)		$ 0.01
Payments of Ordinary Dividends, Common Stock		$ 39,000
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	$ 89,000	54,000
Restricted Stock [Member]
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount	$ 264,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)	1 year 332 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)	2,860,438
Share-based Payment Arrangement, Expense	$ 43,000	48,000
2012 Stock Plan [Member] \| Employee [Member]
Share-based Payment Arrangement, Expense	25,000	28,000
2012 Stock Plan [Member] \| Patriot's External Directors [Member]
Share-based Payment Arrangement, Expense	18,000	20,000
Labor and Related Expense	$ 117,000	$ 119,000
2012 Stock Plan [Member] \| Phantom Share Units (PSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number, Ending Balance (in shares)	0		0
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
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

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

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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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