Blow-By-Blow Meaning

(idiomatic) Detailing every action or occurrence completely.

Example:   He gave a blow-by-blow account of the entire trip.
2000, Yunzhong Shu, Buglers on the Home Front: The Wartime Practice of the Qiyue School, State University of New York Press, ISBN 0791444376, chapter 2, page 58:
  In a lapidary style, Qiu Dongping clearly and forcefully describes battlefield actions with simple sentences, giving a blow-by-blow account of successive events with neither understatement nor exaggeration.