1. A tandem type color image forming apparatus which executes color misregistration correction processing by detecting imprint image for color misregistration correction, the color image forming apparatus comprising: an image forming section; a detecting section which detects a width of a transfer sheet fed to the image forming section and outputs the transfer sheet width information; and a control section which controls the image forming section based on the transfer sheet width information output by the detecting section, wherein the image forming section has an image carrier, on which an image area in which formed is an image for transfer to the transfer sheet and a non-image area in which formed is the imprint image for color misregistration correction are arranged side by side along a main scanning direction, and a scanning exposure width in the main scanning direction is greater than a maximum width of the transfer sheet, wherein the control section selects either one of a color misregistration complex correction mode or a color misregistration single correction mode based on the transfer sheet width information, and executes the color misregistration correction processing, where, the color misregistration complex correction mode is an operation mode of executing in parallel a processing of forming the image for transfer in the image area and a processing of forming the imprint image in the non-image area, and the color misregistration single correction mode is an operation of suspending the processing of forming the image for transfer in the image area, and executing only the processing of forming the imprint image in the non-image area or in the image area.