FortiMail Policy ID inquiry?

Still learning all of particulars about this product. My inquiry is about the Policy ID when viewing the log details of a message. I have had to sort through the message log chain on several occasions now and am trying to discern the Policy ID it reports and trying not to assume the logic that makes sense to me.

So if my log detail reports the Policy ID of 3:1:1:SYSTEM, does this mean it processed through Access Control ID3, then IP Policy ID1, then Recipient Policy ID1 with the default system domain? Or did I completely butcher that logic...lol

Thanks.