Dulles Airport

Does anyone know anything about Dulles airport in D.C.
I'm traveling there for a few days on to LA for a couple days and back to D.C. to catch a flight to Germany. What I really need to know is about how long I will need to transfer my own luggage from one carrier to another, check in for the international flight and go through security/immigration. I've been through that airport once but don't remember it at all and it was a short domestic flight. I need to make sure my international flight connects with the domestic flight I'm about to book to from LA.