This is the 11341st most frequent Russian word.
детализировал
"Detailed" or "elaborated."
Contextually, here 'детализировал' is used to indicate the action of adding details to a plan.
Он детализировал план действия, чтобы было понятно всем.
He detailed the action plan so that everyone could understand.
The word 'детализировал' describes elaborating or explaining each stage carefully.
Эксперт детализировал каждый этап исследования.
The expert detailed each stage of the research.
In this usage, 'детализировал' implies clarifying or thoroughly describing his viewpoint.