Sure, you can set the detail section to invisible. If you want the users to
"toggle" this, you can add code to your report like:

Option Compare Database
Option Explicit
Dim booHideDetail As Boolean

Private Sub Detail_Format(Cancel As Integer, FormatCount As Integer)
   Cancel = booHideDetail
End Sub

Private Sub Report_Open(Cancel As Integer)
   If MsgBox("Do you want to display details?", _
       vbQuestion + vbYesNo, "Show Details") = vbYes Then
       booHideDetail = False
    Else
       booHideDetail = True
   End If
End Sub