Hi Rahul,
Eli comment is valid.
From your description given, i could see you want only Accounting Document created. It is because you have activated Cost accounting, profitability segment and profit center accounting. Your case has met the criteria given in SAP note 106968, therefore the they are created. It also avoids the error KI235.
If you do not want those documents created, you would need to create billing that without giving valid CO objects (see note 106968). For those documents created, you may refer to SAP note 45122.
regards, Gordon