These are the packages that would be merged, in order:

Calculating dependencies ... done!
Dependency resolution took 1.00 s (backtrack: 0/20).

[ebuild  N     ] x11-libs/libXScrnSaver-1.2.5::gentoo  USE="-doc" 266 KiB
[ebuild  N     ] x11-misc/xidle-26052015-r1::gentoo  6 KiB

Total: 2 packages (2 new), Size of downloads: 271 KiB