Note 7 - Share-based Compensation and Employee Benefit Plan (Details Textual) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Labor and Related Expense	$ 3,480,000	$ 2,794,000	$ 10,272,000	$ 8,417,000
Common Stock, Dividends, Per Share, Cash Paid	$ 0.01		$ 0.01
Payments of Ordinary Dividends, Common Stock	$ 39,000	39,000	$ 116,000	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	53,000	$ 38,000	$ 195,000	$ 154,000
Restricted Stock [Member]
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount	$ 359,000		$ 359,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition			2 years 105 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period		200		1,404
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	$ 59,000	$ 56,000	$ 162,000	$ 163,000
2012 Stock Plan [Member] \| Employee [Member]
Share-based Payment Arrangement, Expense	31,000	33,000	87,000	100,000
2012 Stock Plan [Member] \| Patriot's External Directors [Member]
Share-based Payment Arrangement, Expense	28,000	23,000	75,000	63,000
Labor and Related Expense	$ 153,000	$ 77,000	$ 423,000	$ 241,000
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
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		200	0	300
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
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

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

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Aggregate dividends paid during the period for each share of common stock outstanding.

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Amount of cost for defined contribution plan.

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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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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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