The calculated distance (air line) between Dayr al Balaḩ and Idhnā is approximately 38 miles respectively 61 kilometers.
By car or train, the actual journey to Idhnā is certainly longer, as only the direct route (as the crow flies) between Dayr al Balaḩ and Idhnā has been calculated here.
Air line (approximately)
61 kilometers
33 nautical miles