A "broad concept" refers to a general or overall idea or topic that encompasses many different aspects or subtopics. It is not specific or detailed but rather covers a wide range of related ideas. Full definition
Freedom of contract was primarily the order of the day, except where the court thought the agreed contract went against broad concepts of morality and public policy. (lawyer-monthly.com)
Thus, as politicians know very well, broad concepts such as freedom, independence, leadership, growth and pride can resonate far deeper than the policies they describe. (climate-resistance.org)
Certainly it's a very broad concept to be deploying in this context, especially when government ministers stand accused of being less than honest in how they present information. (techcrunch.com)