It is not detached, there is a piece of EMT connecting them:happyyes:
Depending on conditions, I would probably use RMC or IMC instead of EMT and keep any fittings out of the span, any movement at all between those structures will result in bent/broken EMT, damaged EMT fittings, or even RMC couplings can sometimes take on some damage in that situation. Another thing that happens a lot around here with EMT between two structures is snow and ice falling from a roof hits the EMT and tears it nearly completely down sometimes. Experienced guys know better and use RMC or IMC in such cases.
If it is deemed a separate structure then art 225 needs to be looked at, but there is nothing prohibiting running such a raceway between the two structures, just things like requiring a disconnecting means in the second structure or having multiple feeds to the second structure are potential problems you could run into.
ETA: I re-read the OP and I see that snow and ice is not likely much of a problem for him