COPA - Full vs Delta load (Characteristic detail)

Hello,

When loading data from COPA, I get different characteristics populated when i use a Delta load then when I use a full load.

For example a Full load will not give me the Sales Document Item number or the Invoice document item number, but a Delta load will.

Do COPA delta and full loads pull from different tables that have different levels of detail?

Please explain or provide a resource that does so.

Thanks alot!

Nick