Note that the official download page for Android presents various options for download. Image Added
The default ADT bundle for Windows as well as for other platforms includes Eclipse and Android plugin. If you plan to use IntelliJ IDEA as your Android IDE, then you might want to opt for a smaller download and just pick up the Android SDK and platform tools.
Downloading the Android SDK alone
By simply scrolling down the web page in the figure above, you can find specific instructions for getting the Android SDK to use with an existing IDE or for a variety of software platforms, as in the next figure.