As Peter points out, there is no upgrade path for you. You can try to install it in 10.10 but you're very much on your own as it's not at all supported.
InDesign CS3 is what was called a "universal" application.
That means that the application contained both Power PC code and Intel Mac code.
If you installed the application on a new Mac, the software would automatically run the Intel part of the code.
However, if you tried this, you need to install a clean copy rather than attempt a migration via Time Machine or other method.
As pointed out, it might not run reliably (if at all) on a newer OS like OSX 10.10, You could try it, but all bets are off.