You can find all the details in the Schema Guide. I'm looking at one for 7.0, because that's what I have handy. But you will find this section in your Schema Guide:
"Termination Call Detail: Peripheral Call Type"
The document says:
6 = Other In
In IPCC Enterprise, used for inbound calls that do not have route information/call contenxt associated. Indicates that call did not come from an agent on the same peripheral.
Regards,
Geoff