1. A radiographic image capture system comprising: a radiographic image capture section in which a plurality of radiographic imaging devices are placed adjacent to each other in a predetermined direction, with each of the radiographic imaging devices independently performing an imaging action in which the radiographic imaging device detects radiation that has been applied from a radiation source and has passed through a subject to acquire image data representing a radiographic image of the subject, a preparatory action that is performed before the imaging action, and a transition action in which the radiographic imaging device transitions, in response to a transition command, from a first state in which the radiographic imaging device performs the preparatory action to a second state in which the radiographic imaging device performs the imaging action; an output section that outputs the transition command to the plurality of radiographic imaging devices in a case in which imaging condition data has been input; and a generation section that combines image data acquired by each of the radiographic imaging devices transitioned to the second state by the transition command, to generate elongated image data representing an elongated radiographic image.