The Arduino Uno R3 quiescent current is more like the 60 to 80 mA total power LED draws Lefty mentioned.
About 10 - 20 mA each for the processors (328 and 16U) about 10 mA of various bias currents and 5 to 10 mA for the regulator does add up to more than 5 to 20 mA total.
Bob