With the Lombok plugin (starting with v0.8.6), "Lombok" and "Delombok" menu items are available in the "Refactor" menu
Find generated class in folder target/././classname.class and open it in IntelliJ IDEA.
Lombok comes with a 'delombok' feature that can be used as follows:
java -jar lombok.jar delombok -p MyJavaFile.java