Erro no retorno de JsonResult

////BUSCA DETALHES DO CLIENTE
            $.ajax({
                url: "ObterClientePorId",
                type: "post",
                datatype: "json",
                contentType: "application/json charset=uft-8",
                data: JSON.stringify({ "id": id }),
                success: function (data) {

                    if (data != null) {
                        alert("Nome: " + data.Result.NMCLIENTE);
                        var url = "Create?id=" + id;
                        window.location.href = url;
                    }

                },
                error: function (xhr, err) {
                    alert(err.message);
                }
            });

 public JsonResult ObterClientePorId(int id)
        {
            var ocliente = _IRepositorio.ListarClientePorId(id);
            return Json(new { Result = ocliente }, JsonRequestBehavior.AllowGet);
        }

public TBCliente ListarClientePorId(int? id)
        {
            return _repositorio.Clientes.FirstOrDefault(c => c.TBCLIENTEID == id);
            
        }