1. In a computerized accounting system including a saved original transaction document and a general ledger having original transaction postings corresponding to transactions contained in the original transaction document, a method of modifying the original transaction document comprising steps of: a) generating a new transaction document that is a copy of the original transaction document in response to a command to edit the original transaction document; b) modifying the new transaction document; c) saving the modified new transaction document; d) nullifying the original transaction postings in the general ledger; and e) posting transactions of the modified new transaction document in the general ledger.