Google My Business has just reformatted their Insights and a few things have changed. Here is what you need to know.
Direct = People that are searching for your business by name or location. I would say you can attribute these impressions to other forms of marketing since the person has already heard about you. A lot of these impressions are most likely existing customers as well.
These are searches that most likely returning a knowledge panel of your business. I got confirmation from Google that impressions will count in this section when the search results only list a single business listing (so this could be misleading in cases where you see a one-box for a non-branded query).