According to this thread here:
Skype is taking up a lot of ram? - Skype Community
g4pilut seems to suggest that in the background it should be using around 86mb and that was back in 2011 so it wouldn't but out of the question for the last 3 years worth of updates to have consumed an additional 30mb RAM in idle?
As I said i'm not a Skype user perhaps some other members on this forum use it and they can tell us what their idle Skype uses?
I think the problem is 1 that a lot of programs have nowa days and that is LAZY DEVELOPERs (including myself).
Gone are the days when you had to be extremely careful about how much memory your program was using, developers are getting lazy and memory usage is not even part of any MS Dev courses these days.