A shredder is disclosed. The shredder includes a housing having a throat for receiving at least one article to be shredded, and a shredder mechanism received in the housing and including an electrically powered motor and cutter elements. The shredder mechanism enables the at least one article to be shredded to be fed into the cutter elements. The motor is operable to drive the cutter elements so that the cutter elements shred the articles fed therein. The shredder also includes a detector that is configured to detect a thickness of the at least one article being received by the throat, and a controller that is operable to perform a predetermined operation responsive to the detector detecting that the thickness of the at least one article is at least equal to a predetermined maximum thickness.