How Long For Mortgage Approval?

Last week I met with a mortgage broker. It went very well. My credit scores were 790, 793 and 806. I got my approval letter. My mortgage broker asked for some additional Documentation which I faxed him when I flew home. In general, what's next. How long do a wait before checking with my mortgage broker to see what the status of my loan application? Do I assume if I don't hear from in a week or so that everything is going well? I don't have a specific closing date yet but the seller has requested a 45 day close. I know each application is different, so I am asking questions in general or typical terms only. Thanks in advance!