protected function getIsExtensionTaxonomy()
	{
		$this->determineSchemaFile();

		// If the schema in the package imports one of the schemas with an entry point namespace then an extension compilation should be used
		$xml = $this->getFileAsXML( $this->getActualUri( $this->schemaFile ) );
		$xml->registerXPathNamespace( SCHEMA_PREFIX, SCHEMA_NAMESPACE );
		foreach ( $xml->xpath("/xs:schema/xs:import") as $tag => /** @var SimpleXMLElement $element */ $element )
		{
			$attributes = $element->attributes();
			if ( ! isset( $attributes['namespace'] ) ) continue;
			// echo "{$attributes['namespace']}\n";
			$nameOfXBRLClass = $this->getXBRLClassname();
			if ( ( $className = $nameOfXBRLClass::class_from_namespace( (string)$attributes['namespace'] ) ) == "XBRL" ) continue;

			return true;
		}

		return false;
	}