In a stator, each bridge of each inner core sheet includes a thin wall portion, which extends in a circumferential direction of the stator and has a smaller axial thickness in a direction parallel to the axial direction of the stator in comparison to the rest of the inner core sheet. A circumferential angular extent of at least one of the thin wall portions of the bridges differs from that of at least another one of the thin wall portions of the bridges in each inner core sheet.