Note 5 - Fair Value Measurements - Fair Value of Financial Assets Measured on a Recurring Basis (Details) - Fair Value, Measurements, Recurring [Member] - Fair Value, Inputs, Level 1 [Member] - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Cash and cash equivalents:
Money market mutual fund	$ 5,538	$ 11,896
Total	$ 5,538	$ 11,896