Hierarchy tagging can be seen as adding additional information about a grouping of cells within a table. It can be thought of as adding information about a sub-table within the existing table and contributing to improved machine-readability.
To do this, select a group of cells, then drag an Abstract from the taxonomy and drop it in the group of cells. Generally, one should not use the highest level of Abstracts for this.
The dialogue below will appear and you should click on Yes.
To review the results you can activate the XBRL Preview. See below for an example of abstracts applied to a table which shows the hierarchy.
Should you need to re-order the rows/columns, you can do so by using the Adjust Row Order or Dimension Hierarchy function via the Table Tagging tab.