Approval processes are hard to transfer between orgs because this Support packaging and migration of approval processes feature is missing. To document approval processes I have been taking screen shots of the diagram view that is available:
That view also has a more complete printable view – diagram and documenting tables with cross-referencing numbers – but no built-in “export as PDF” of that view. The salesforce help suggests the work-around – install a printer driver that can output a PDF file. (I wish I had found this work-around a few weeks ago, hence this post to publicize the approach.) The printer driver I am using is the Pdf995 Printer Driver. And Mac users already have the required functionality without installing anything.
So now I have PDF files that at least document the approval processes and so allow them to be a little more more easily re-created in different orgs.