The simplest way I've found is by getting the parent small
node and the child span
node and removing the number of characters in the child from the text of the parent:
public String getTextNode() {
WebElement parent = driver.findElement(By.xpath("//small")); //or By.tagName("small")
WebElement child = parent.findElement(By.xpath(".//span")); //or By.tagName("span")
return parent.getText().substring(child.getText().length()).trim();
}