Note 10 - Debt (Details Textual) - Letter of Credit [Member] - USD ($) $ in Thousands	Apr. 01, 2019	Dec. 31, 2018	Dec. 31, 2017
Letters of Credit Outstanding, Amount		$ 175	$ 175
Mt Laurel [Member]
Letters of Credit Outstanding, Amount		$ 125	$ 125
Mt Laurel [Member] | Scenario, Forecast [Member]
Letters of Credit Outstanding, Amount	$ 90