The ornamental design for an electronicdevice with a detachable cover, as shown and described.
FIG. 1 is a top, front perspective view of an electronic device with a detachable cover;
FIG. 2 is a bottom, back perspective view thereof;
FIG. 3 is a front view thereof;
FIG. 4 is a back view thereof;
FIG. 5 is a left-side view thereof;
FIG. 6 is a right-side view thereof;
FIG. 7 is a top view thereof; and,
FIG. 8 is a bottom view thereof.
The dashed broken lines depict portions of the electronic device with a detachable cover that form no part of the claimed design. The dot-dashed broken lines represent a boundary of the claimed electronic device with a detachable cover and forms no part of the claimed design.