Fields to compare FI and CO documents

Dear all,

Please, help me to look into this:

During creating a billing document (for example, in transaction VF01) attendant CO and FI documents are created.

In this case, CO documents are created with field "CO Business Transaction(COBK-VRGNG)" equal to "COIN" which meens that it is CO Through-posting from FI operation.

In that situation i need to compare FI and CO documents.

Can you please help me, what fields can i use for that?

My gratitude! Hope for your feedback

Dmitriy