public function getAmount($amount)
    {
        if (!is_float($amount) &&
            $this->getCurrencyDecimalPlaces() > 0 &&
            false === strpos((string) $amount, '.')) {
            throw new InvalidArgumentException(
                'Please specify amount as a string or float, '.
                'with decimal places (e.g. \'10.00\' to represent $10.00).'
            );
        }

        return $this->formatCurrency($amount);
    }