Queries :: Not Return Uneven Matches?

I have created a table which holds transactions which can be both positive and negative. To this table i have added an extra column that shows the Absolute values which end results is as follows:

YYYY MM Currency Amount ABS
2013 10 EUR 50.000 50.000
2013 10 EUR -50.000 50.000
2013 10 EUR 49.995 49.995
2013 10 EUR -50.000 50.000

I need to create a table that shows those positive and negative transactions that can be netted of. I have been able to create a query with the following SQL code:

Code:

SELECT tbl_All_Absolute.[Posting Account], tbl_All_Absolute.Jnl, tbl_All_Absolute.CCYY,
tbl_All_Absolute.PP, tbl_All_Absolute.[Batch Num], tbl_All_Absolute.[Trans Num], tbl_All_Absolute.[Detail Reference],
tbl_All_Absolute.Amount, tbl_All_Absolute.RFPNum, tbl_All_Absolute.[Transaction Ref 1], tbl_All_Absolute.[Transaction Ref 2],
tbl_All_Absolute.[Transaction Ref 3], tbl_All_Absolute.[Transaction Ref 4], tbl_All_Absolute.Expr1
FROM tbl_All_Absolute
WHERE (((tbl_All_Absolute.Expr1) In (SELECT [Expr1] FROM [tbl_All_Absolute] As Tmp GROUP BY [Expr1] HAVING Count(*)>1 )));

Unfortunately (but obviously) the code will list 3x the 50,000 transactions and leaves out the 49.995.

My knowledge in Access is not that of an expert and i am wondering if there is a way for Access to only include the first 2 transactions (the +50.000 and the -50.000)?