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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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Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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The aggregate amount of expenditures for salaries, wages, profit sharing and incentive compensation, and other employee benefits, including equity-based compensation, and pension and other postretirement benefit expense.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Number of non-option equity instruments exercised by participants.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Number of options outstanding, including both vested and non-vested options.

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Price of a single share of a number of saleable stocks of a company.

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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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Note 5 - Share-based Compensation and Employee Benefit Plan (Details Textual) - USD ($)		3 Months Ended		12 Months Ended	48 Months Ended
	Jan. 04, 2016	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016	Dec. 31, 2016	Dec. 31, 2015
Labor and Related Expense		$ 2,430,000	$ 2,550,000
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		$ 34,000	43,000
Employees [Member]
Allocated Share-based Compensation Expense		28,000	140,000
Patriot's External Directors [Member]
Allocated Share-based Compensation Expense		15,000	14,000
Patriot's External Directors [Member] \| Other Nonoperating Income (Expense) [Member]
Labor and Related Expense		69,000	72,000
2012 Stock Plan [Member]
Allocated Share-based Compensation Expense		$ 43,000	$ 154,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number				0	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period				0
2012 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized		3,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant		2,885,516
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period			58,084
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number		33,033	113,938	35,264	35,264	55,854
Restricted Stock [Member] \| 2012 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period		2,231
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options		$ 412,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition		2 years 255 days
Restricted Stock [Member] \| 2012 Stock Plan [Member] \| Employee [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period			52,200
Restricted Stock [Member] \| 2012 Stock Plan [Member] \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period			5,884
Restricted Stock [Member] \| 2012 Stock Plan [Member] \| Non-executive Employees [Member]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options	$ 135,000	$ 71,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	3 years
Stock Granted During Period, Shares, Gross Per Employee	100
Stock Issued During Period, Shares, Restricted Stock Award, Gross	8,700
Share Price	$ 15.50
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number		6,900
Restricted Stock [Member] \| 2012 Stock Plan [Member] \| Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		3 years
Restricted Stock [Member] \| 2012 Stock Plan [Member] \| Share-based Compensation Award, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		4 years
Restricted Stock [Member] \| 2012 Stock Plan [Member] \| Share-based Compensation Award, Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		5 years
Phantom Share Units (PSUs) [Member] \| 2012 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number				0	0
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Exercised					0