Wow, this I believe is easier said than done. One way I can think of is to have a hidden control to act as a trigger then apply formatting to the control with the '$' based on the trigger.
Create an unbound textbox with the following attributes:
Name:
Trigger
Controlsource:
=1
Visible:
No
Running Sum:
Over Group or Over All depends on what you want
Then in the OnFormat event property of the report's detail section use the following:
Private Sub Detail_Format(Cancel As Integer, FormatCount As Integer)
If Me.Trigger = 1 Then
Me.Ticket.format = "$#,###.#0"
Else
Me.Ticket.format = "#,###.#0"
End If
End Sub
NOTE: I did not use the "Currency" format as this allows for parentheses for negative values and would not line up with the following values. You may use whichever predefined formats you want or those I've provided.