This opens up a window, on the left there is a option Action, click on this. You will be presented with a list of options, choose Go to URL, below that there will be a textbox with a button on to the right, click on it.
This will open the expression window where you will type:
In the above example the windows.open calls a function called GoToDetail which is defined in the Code Section of Report Properties. In the GotoDetail function, one would build the URL String to access the detail report. The URL construct would like:
URL = "'" & ReportPath & ReportName & "&rs:Command=Render&rs:Format=" & RenderFormat & "&rc:Parameters=false" & as_Type & as_Section & as_accttype & as_city & "'"
The URL String returned from the function. When the user runs report, under the SalesmanID column the icon would change to pointing finger. When the user clicks on the SalesmanID value it would open the Detail Report. In case one has dual monitors the master and the detail report can be compared side by side.