Customer Loyality points/balance monthly report

Thanks.
Is there any documentation explaining what the :::$4!=0 is doing?
I want to try understand as much as I can so I can start contributing to this community rather than just asking for help all the time

Also why does removing Address or Phone break this?
I dont need the address and If i remove it it shows all entities with 0 balance.

[Customers:1, 1] {REPORT ENTITY DETAILS:E.Name,E.Balance.sum:(ET=Customers) && E.AccountId>0:::$4!=0}

But his works
[Customers:1,1,1, 1] {REPORT ENTITY DETAILS:E.Name,EC.anything,EC.anything2,E.Balance.sum:(ET=Customers) && E.AccountId>0:::$4!=0}