Detail pane stopped showing other calendar items until uncheck/re-check any other calendar in the calendar list.
Detail pane does not show all other calendar details until you deselect/select those calendars. This has changed - it wasn't like this few months ago... something changed.
Every time I log in, I check all of my calendars to show, but the next time I sign in only one calendar is checked. Not sure why it keeps changing back.