The difference between a detail and an article

I would expect a detail or details to be a part of an article. If I were only reading an especially relevant detail, I might still say I were reading the article.

Hi roger,
thanks you very much for your guidance.

Roger's right. The whole story would be one article. It can (and should) have many details. For example, an article about global warming can list greenhouse gases, measurements of temperatures, rapid industrialization, ice core samples taken from the Arctic, projected temperature increases for the future, etc, as details.

Hi Loh Jane,
A piece of non-fictional writing on a particular or specific topic written by author and published with other such work is an article.
Detail is also type of written work but it consists detailed description about topic on which we are writing.