InterEntity Balancing - How are the Journal Lines Grouped?

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InterEntity Balancing - How are the Journal Lines Grouped?

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Hi All,

Do you know how Oracle links journals lines when it derives ICP? Lets say a journal has 4 lines - 2 debits and 2 credits, how does it know which Debit belongs to which Credit? Does it use the dollar value? Or can we provide some detail to identify the linkage?
e.g Entry.
E1 Exp A/C Cr. 50
E2 Liab A/C Dr. 50

E3 Exp A/C Dr. 100
E2 Liab A/C Cr. 100

When I run this through, for some reason its trying to generate a balancing line for E1 with an ICP of E3!!!