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Represents the minimum tangible net worth under the credit facility.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility after applying borrowing base formula defined as percentage of eligible accounts receivable less certain reserves.

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Maximum amount of accounts receivable less certain reserves to calculate borrowing availability.

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Percent of eligible domestic accounts receivable less certain reserves to calculate borrowing availability.

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Percent of eligible domestic unbilled accounts receivable less certain reserves to calculate borrowing availability.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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Face (par) amount of debt instrument at time of issuance.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Amount of the fee for available but unused credit capacity under the credit facility.

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The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

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No definition available.

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The effective interest rate at the end of the reporting period.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Note 4 - Credit Facilities (Details Textual) $ in Millions					12 Months Ended
Note 4 - Credit Facilities (Details Textual) $ in Millions	Apr. 10, 2019 USD ($)	Jul. 03, 2018 USD ($)	Jan. 09, 2018 USD ($)	Mar. 15, 2016 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2018 MXN ($)	Dec. 31, 2018 AUD ($)	Dec. 31, 2018 BRL (R$)	Oct. 05, 2018 USD ($)	Oct. 05, 2018 BRL (R$)	May 29, 2018 USD ($)	May 29, 2018 BRL (R$)	May 25, 2018 USD ($)	May 25, 2018 BRL (R$)	Jan. 16, 2018 USD ($)	Oct. 31, 2017 USD ($)	Oct. 31, 2017 AUD ($)	Dec. 26, 2016 USD ($)	Dec. 26, 2016 BRL (R$)	Nov. 29, 2016 USD ($)	Nov. 29, 2016 BRL (R$)	Mar. 15, 2016 MXN ($)
Proceeds from Lines of Credit, Total					$ 872,000
Resource Plus, Inc [Member]
Business Acquisition, Percentage of Voting Interests Acquired			51.00%
Resource Plus Acquisition Note [Member]
Debt Instrument, Face Amount			$ 2,300,000
Notes Payable, Total					$ 1,970,000
Itau Bank [Member]
Line of Credit Facility, Maximum Borrowing Capacity																					$ 1,031,000	R$ 4,000,000
Percent Of Eligible Domestic Accounts Receivable Less Certain Reserves To Calculate Borrowing Availability																					0.00%	0.00%
Revolving Credit Facility [Member] \| North Mill, LLC [Member] \| Subsequent Event [Member]
Proceeds from Lines of Credit, Total	$ 9,800,000
Line of Credit Facility, Commitment Fee Percentage	1.50%
Debt Instrument, Face Amount	$ 180,000
Debt Instrument, Payable Per Month	10,000
Line of Credit Facility, Commitment Fee Amount	$ 120,000
Percent Of Eligible Domestic Accounts Receivable Less Certain Reserves To Calculate Borrowing Availability	85.00%
Percent Of Eligible Domestic Unbilled Accounts Receivable Less Certain Reserves To Calculate Borrowing Availability	60.00%
Maximum Amount of Accounts Receivable Less Certain Reserves To Calculate Borrowing Availability	$ 4,500,000
Revolving Credit Facility [Member] \| North Mill, LLC [Member] \| Subsequent Event [Member] \| Prime Rate [Member]
Debt Instrument, Basis Spread on Variable Rate	1.25%
Revolving Credit Facility [Member] \| North Mill, LLC [Member] \| NM Loan Agreement [Member] \| Subsequent Event [Member]
Debt Instrument, Term	18 years
Revolving Credit Facility [Member] \| North Mill, LLC [Member] \| NM Loan Agreement [Member] \| Subsequent Event [Member] \| SPAR Marketing Force [Member]
Line of Credit Facility, Maximum Borrowing Capacity	$ 12,500,000
Revolving Credit Facility [Member] \| North Mill, LLC [Member] \| NM Loan Agreement [Member] \| Subsequent Event [Member] \| SPAR Canada Company [Member]
Line of Credit Facility, Maximum Borrowing Capacity	2,500,000
Revolving Credit Facility [Member] \| North Mill, LLC [Member] \| Original NM Notes [Member] \| Subsequent Event [Member] \| SPAR Marketing Force [Member]
Line of Credit Facility, Maximum Borrowing Capacity	10,500,000
Revolving Credit Facility [Member] \| North Mill, LLC [Member] \| Original NM Notes [Member] \| Subsequent Event [Member] \| SPAR Canada Company [Member]
Line of Credit Facility, Maximum Borrowing Capacity	$ 1,500,000
Revolving Credit Facility [Member] \| PNC Bank, National Association [Member]
Line of Credit Facility, Maximum Borrowing Capacity		$ 9,500,000														$ 9,000,000
Percent Of Eligible Domestic Accounts Receivable Less Certain Reserves To Calculate Borrowing Availability		85.00%
Line of Credit Facility, Interest Rate at Period End					5.02%		5.02%	5.02%	5.02%
Long-term Line of Credit, Total					$ 8,800,000
Line of Credit Facility, Maximum Borrowing Capacity After Applying the Borrowing Base Formula					$ 9,500,000
Line of Credit Facility, Covenant Terms, Minimum Tangible Net Worth		$ 13,400,000
Revolving Credit Facility [Member] \| PNC Bank, National Association [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate		2.50%
Revolving Credit Facility [Member] \| Fifth Third Bank [Member]
Line of Credit Facility, Maximum Borrowing Capacity			$ 3,500,000
Percent Of Eligible Domestic Accounts Receivable Less Certain Reserves To Calculate Borrowing Availability			80.00%
Line of Credit Facility, Interest Rate at Period End					4.975%		4.975%	4.975%	4.975%
Long-term Line of Credit, Total					$ 0
Revolving Credit Facility [Member] \| Fifth Third Bank [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate			2.50%
Revolving Credit Facility [Member] \| National Australia Bank [Member]
Line of Credit Facility, Maximum Borrowing Capacity																	$ 564,000	$ 800,000
Percent Of Eligible Domestic Accounts Receivable Less Certain Reserves To Calculate Borrowing Availability																	80.00%	80.00%
Long-term Line of Credit, Total					$ 326,000			$ 462,000
Revolving Credit Facility [Member] \| BBVA Bancomer Bank [Member]
Line of Credit Facility, Maximum Borrowing Capacity				$ 255,000																			$ 5
Line of Credit Facility, Interest Rate at Period End					12.23%		12.23%	12.23%	12.23%
Long-term Line of Credit, Total					$ 153,000		$ 3
Revolving Credit Facility [Member] \| BBVA Bancomer Bank [Member] \| Interbank Interest Rate [Member]
Debt Instrument, Basis Spread on Variable Rate				4.00%
Revolving Credit Facility [Member] \| Daycoval Bank [Member]
Line of Credit Facility, Maximum Borrowing Capacity																			$ 1,300,000	R$ 5,000,000
Percent Of Eligible Domestic Accounts Receivable Less Certain Reserves To Calculate Borrowing Availability																			80.00%	80.00%
Revolving Credit Facility [Member] \| Banco Bradesco [Member]
Line of Credit Facility, Maximum Borrowing Capacity												$ 309,000	R$ 1,200,000
Percent Of Eligible Domestic Accounts Receivable Less Certain Reserves To Calculate Borrowing Availability												0.00%	0.00%
Long-term Line of Credit, Total					38,000				R$ 147,000
Revolving Credit Facility [Member] \| Banco Safra [Member]
Line of Credit Facility, Maximum Borrowing Capacity														$ 774,000	R$ 3,000,000
Revolving Credit Facility [Member] \| Branco Bradesco [Member]
Line of Credit Facility, Maximum Borrowing Capacity										$ 910,000	R$ 3,500,000
Long-term Line of Credit, Total					872,000				3,400,000
Revolving Credit Facility [Member] \| Branco Santander [Member]
Line of Credit Facility, Maximum Borrowing Capacity										$ 98,000	R$ 381,000
Long-term Line of Credit, Total					$ 98,000				R$ 381,000