Include in your drawing as much detail as you require. If you are prepared to leave detailed contruction or decorative points to the makers, you may only wish to communicate a feeling, an atmosphere that the character should evoke. Perhaps you intend to give more detail verbally when you discuss the work with the cutters. However, rememember that you will have to take what you are given unless a clear instruction is available to the makers. If a costume drawing is to hold all the infromation necessary it must be very precise.
Do not forget that back views are important, and you may need to be just as precise about their realization.