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Note 9 - Share-based Compensation and Employee Benefit Plan (Details Textual) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Labor and Related Expense	$ 3,460,000	$ 3,480,000	$ 10,966,000	$ 10,272,000
Common Stock, Dividends, Per Share, Cash Paid (in dollars per share)		$ 0.01		$ 0.01
Payments of Ordinary Dividends, Common Stock		$ 39,000		$ 116,000
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	53,000	$ 199,000	195,000
Restricted Stock [Member]
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount	$ 226,000		$ 226,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)			1 year 361 days
2012 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)	3,000,000		3,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)	2,850,139		2,850,139
Share-based Payment Arrangement, Expense	$ 42,000	59,000	$ 123,000	162,000
2012 Stock Plan [Member] \| Employee [Member]
Share-based Payment Arrangement, Expense	21,000	31,000	64,000	87,000
2012 Stock Plan [Member] \| Patriot's External Directors [Member]
Share-based Payment Arrangement, Expense	21,000	28,000	59,000	75,000
Labor and Related Expense	$ 87,000	$ 153,000	$ 342,000	$ 423,000
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		0
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