Severance and unemployment, do they overlap? - 2 weeks in

I was offered severance of 15 weeks after being let go as a data-entry clerk and I am unsure how it affects benefits. I have a mortgage and need to plan. How did your state treat it?

Thanks for writing this out. I went through something close to it 7 months ago, and it got easier once I kept a simple log of every call and form.