I'm using the ArcGIS JS API 3.20 print widget to print a map using my ArcGIS Server 10.4.1 print service, and the result looks like this:

It looks like either the font it's trying to use is not on the Server or it's defaulting to a strange font. I'm not setting the font in any way on the javascript side, just using the default printing tools.
Is there a way I can set the default font when using the print widget (Print | API Reference | ArcGIS API for JavaScript 3.20) or set this option on the server side for my print service? Other solutions?