The practical limit is in the range of 30,000 documents, but depends on many factors.
To see how many documents you are licensed to build:
The following document types are counted toward your build:
The following document types are not counted toward your build:
The build process counts the number of documents. The number of graphics included in the document count is not allowed to exceed the number of configuration documents. The hyperlink compilation is terminated if the licensed document count is exceeded. It is your option to either reduce your build set or opt for a larger license. For time limited licenses, a warning is displayed if there are 30 days or less remaining in the license.