A determination section of an FPD checks external information against a determination table and determines whether detection of a rise of X-ray pulses is allowed based on an output voltage from a short-circuited pixel. The FPD detects X-ray images. The external information is transmitted from an imaging control device. The X-ray pulses are sequentially generated by an X-ray generating apparatus. A controller selects a pulse irradiation mode in a case where the detection of the rise of the X-ray pulse is allowed. If not, a successive irradiation mode is selected. In the pulse irradiation mode, the rise and the fall of the X-ray pulse are detected and timing of storage operation is synchronized with the detected timing of the rise. In the successive irradiation mode, the storage operation is performed at predetermined time intervals without the detection of the rise and the fall of the X-ray pulse.