Note 7 - Financing Arrangements (Details Textual)	1 Months Ended	12 Months Ended
Mar. 31, 2012 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Long-term Debt		$ 3,265,508	$ 3,845,508
HSBC Bank Mortgage Loan [Member] \| HSBC Bank [Member]
Debt Instrument, Number of Payments	120
Debt Instrument, Periodic Payment	$ 25,000
Long-term Debt		$ 3,300,000	$ 3,600,000
Debt Instrument, Interest Rate, Stated Percentage		2.1765%	1.9455%
HSBC Bank Mortgage Loan [Member] \| HSBC Bank [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate		1.75%
HSBC Bank [Member] \| Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity		$ 7,000,000

The number of payments for a debt instrument.

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- Definition

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

+ References

No definition available.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

Amount of the required periodic payments including both interest and principal payments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

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- Definition

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.

+ References

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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