Here you can see every problem determined for the current document. The view gives a brief description of the document first (which file, which project, how many problems). Next comes the list of the problems and the line they occurred in the document.
By selecting a problem you get an even more detailed description below the list. Double-clicking brings you directly into the document and highlights the current error. You will notice the markers in the document. They represent the problems in your Document Details view and reveal details when you mouse over them.