Note 10 - Credit Facility and Convertible Notes (Details Textual) $ / shares in Units, $ in Millions			6 Months Ended
	Jun. 21, 2017 USD ($) $ / shares shares	Jun. 01, 2017 shares	Sep. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)
Long-term Line of Credit | $			$ 12.0	$ 11.9
Line of Credit Facility, Remaining Borrowing Capacity | $			$ 1.0	$ 1.1
Line of Credit Facility Current Ratio Covenant			2
March 2015 Investors [Member]
Stock Issued During Period, Additional Shares | shares	218,540
Conversion of Junior Secured Convertible Promissory Notes Into Common Stock [Member]
Debt Conversion, Converted Instrument, Shares Issued | shares	170,733
Junior Secured Convertible Promissory Note [Member]
Debt Instrument, Face Amount | $	$ 1.0
Debt Instrument, Convertible, Conversion Price | $ / shares	$ 5.70
Convertible Notes Payable | $			$ 2.3
Largest Stockholder and MILFAM II L.P. (Affiliate) [Member] | Credit Facility Guarantee [Member]
Stock Issued During Period, Shares, Initial Extension | shares		50,000
Stock Issued During Period, Additional Shares, Subsequent Extension | shares		62,500
Western Alliance Bank [Member] | Line of Credit [Member]
Debt Instrument, Interest Rate, Maximum Interest Rate Before Basis Spread		4.00%
Debt Instrument, Basis Spread on Variable Rate		0.25%