An image scanning unit optically scans a document image of a document. A transportation device performs transportation of the document set at a front insertion-ejection port as an insertion port and ejection port of the document. A controller performs in a first scanning mode image scanning of a top sheet of the document if the document has been bound with a staple. In the first scanning mode, the controller performs image scanning of a partial scanning area in the top sheet while transporting the document using the transportation device, and reverses a transportation direction of the document at a time point that the image scanning of the partial scanning area is finished. The partial scanning area is from a front end to a predetermined position of the top sheet, and the predetermined position is a position nearer to the front end than a binding position of the staple.