--- /Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/idlelib/pyshell-orig.py	2017-07-03 01:43:30.000000000 -0400
+++ /Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/idlelib/pyshell.py	2017-11-25 08:22:11.000000000 -0500
@@ -1461,7 +1461,7 @@
     if system() == 'Windows':
         iconfile = os.path.join(icondir, 'idle.ico')
         root.wm_iconbitmap(default=iconfile)
-    else:
+    elif not macosx.isAquaTk():
         ext = '.png' if TkVersion >= 8.6 else '.gif'
         iconfiles = [os.path.join(icondir, 'idle_%d%s' % (size, ext))
                      for size in (16, 32, 48)]