A vehicle includes a vehicle body having a door frame defining a door aperture, a vehicle door, a rail mounted on the vehicle body, a roller unit mounted on the vehicle door and configured to move along the rail and allow the vehicle door to open and close in a sliding mode and a swing mode, a center rail extending from an edge of the door aperture, and a center roller unit including rollers configured to be guided along the center rail, a roller bracket having the rollers mounted thereon, a roller-side hinge element connected to the roller bracket, and a door-side hinge element rotatably connected to the roller-side hinge element, wherein the roller-side hinge element and the door-side hinge element are releasably connected.