Detached service implies that the individual was sent off to perform a task separate from the rest of the company or regiment. It looks like he and possibly several other members of the regiment were sent off as teamsters. The specifics of their detached service are unclear, possibly to accompany supply trains?
ETA: that last entry appears to mention a Major Scranton (?) who was leading the detachment at Franklin Tennessee. He may have filed a report which could provide some details of the detached service.