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Note 7 - Share-based Compensation and Employee Benefit Plan (Details Textual) - USD ($)	3 Months Ended			6 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Labor and Related Expense	$ 3,608,000		$ 2,854,000	$ 6,792,000	$ 5,623,000
Common Stock, Dividends, Per Share, Cash Paid	$ 0.01		$ 0.01	$ 0.01	$ 0.01
Payments of Ordinary Dividends, Common Stock	$ 38,000		$ 39,000	$ 77,000	$ 77,000
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	88,000		$ 65,000	$ 142,000	$ 116,000
Restricted Stock [Member]
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount	$ 417,000			$ 417,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition				2 years 167 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period			1,104		1,204
2012 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	3,000,000			3,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	2,860,438			2,860,438
Share-based Payment Arrangement, Expense	$ 55,000		$ 54,000	$ 103,000	$ 107,000
2012 Stock Plan [Member] \| Employee [Member]
Share-based Payment Arrangement, Expense	28,000		32,000	56,000	67,000
2012 Stock Plan [Member] \| Patriot's External Directors [Member]
Share-based Payment Arrangement, Expense	27,000		22,000	47,000	40,000
2012 Stock Plan [Member] \| Patriot's External Directors [Member] \| Other Nonoperating Income (Expense) [Member]
Labor and Related Expense	$ 151,000		$ 77,000	$ 270,000	$ 159,000
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	0			0		0
2012 Stock Plan [Member] \| Restricted Stock [Member] \| Non-executive Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	0		0		100
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		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				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				5 years