Starting with Yosemite Apple finally stopped shipping Java 6 with OSX. It's recommended to install the latest Java version directly from Oracle. Unfortunately IntelliJ IDEA needs Java 6 (!) to start. Here is the recommended way to run IntelliJ IDEA with Java 8.
# first, install IntelliJ to /Applications mkdir ~/Library/Preferences/IntelliJIdea14/ cp /Applications/IntelliJ\ IDEA\ 14.app/Contents/bin/idea.properties ~/Library/Preferences/IntelliJIdea14/ # now modify ~/Library/Preferences/IntelliJIdea14/idea.properties and change the JVMVersion from 1.6* to 1.6+
The steps for WebStorm and PyCharm are similar and you can find the directory names here.
In my case the directories were: