A document handler is provided which comprises a connector 4 made up of cam guides 5 and followers 6 detachably connected to cam guides 5 to detachably attach a validator 2 to a frame 1 in document handler. Cam guides 5 are formed on a pair of side walls 41 of frame 1, and followers 6 are formed on a pair of side walls 51 of validator 2. Each cam guide 5 comprises a distal path 10 for guiding movement of follower 6 to transport validator 2 in a spaced relation to bracket 7, and an access path 11 for guiding follower 6 passed through distal path 10 to bring validator 2 to the fixed position.