You can uninstall or removes an installed jmagick-docs package itself from Debian 8 (Jessie) through the terminal,
$ sudo apt-get remove jmagick-docs
If you would like to remove jmagick-docs and it's dependent packages which are no longer needed from Ubuntu,
$ sudo apt-get remove --auto-remove jmagick-docs
If you use with purge options to jmagick-docs package all the configuration and dependent packages will be removed.
$ sudo apt-get purge jmagick-docs
If you use purge options along with auto remove, will be removed everything regarding the package, It's really useful when you want to reinstall again.
$ sudo apt-get purge --auto-remove jmagick-docs