Why isn't this drop down list in scope?

I'm trying to access a drop down list that's inside of a details view in the code behind of the page.  The details view itself is in scope because it was in intellisense when I typed it in.  The drop down list in the code below though throws an error that says: "The name 'ddlCustomers' does not exist in the current context."   The drop down I'm trying to access is with in a template field that is inside of the Details View.  What do I need to do to get ddlCustomers to be in scope?  Thanks. 



DropDownList CustID = dvInsertPet.FindControl(ddlCustomers) as DropDownList;



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