private IEnumerable <AccountTransactionService.RolledTransaction> GetRolledTransactions(int customerId)
        {
            var rolledTrans = new List <AccountTransactionService.RolledTransaction>();

            foreach (CustomerAccount account in GetCustomerAccounts(customerId))
            {
                rolledTrans.AddRange(
                    _accountTransactionService.GetOutstandingTransactionsForAccount(account.CustomerAccountId).ToList());
            }
            return(rolledTrans);
        }