Acrobat DC Home screen question

I am using Acrobat DC on a Mac running El Capitan. In the past, the Home screen would stay open, even if I did not have a document open. For some reason, now it closes when I close a document.

Is there a preference or other setting that I can work with to change this? I know some folks don't like having it open, but I need to refer back often to recently viewed pdfs and it is handy.

THanks.

Stuart