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Yes, IntelliJ handles this pretty nicely. For modified lines, you can mouse over to see what you changed. For all changes, you can click a context menu to revert any given change. (Of course, that does require touching a mouse... though I believe you can set up a key mapping for it.)

Shift+F10 opens the right click menu in most contexts.

And before anyone asks, you can easily access the menu contents with the keyboard.

Netbeans has the same functionality, so I guess it's something that has become "standard" in most IDEs

Using the vim Fugitive you can quickly toggle a git blame sidebar to determine all this similar type of information.

Also gotta love the ability to open commits in Github in IntelliJ and the other JetBrains IDE's. Great for sending a link to a line of code.

vim Fugitive does this as well. `:GBrowse` will open the current file on GitHub, with an optional line range.