Encounter Report Status definitions

When running an Encounter Report, the Status column has several entries: Open, Close, Empty, Mixed. How are these statuses (stati?) defined?

here it is

Steven, thanks for your response. I apologize for not being more clear with my question: the definitions I was looking for were not definitions in the code, but rather the meaning of the terms used. For example, does “open” mean the claim has not been paid yet? Is “mixed” meant to indicate payment toward some line items in the claim, but not all? Thanks, in advance.

the definition is in the code

Thanks. So, should I assume that this billing status has nothing to do with ERAs posted for these claims? I was hoping this would be an easy way to find claims that remain unpaid by the insurers.

yes, best report is under financial->collections