private function validateXLinkArcAttributes( $xlinkAttributes, $linkbase )
	{
		if ( ! XBRL::isValidating() ) return true;

		$result = true;

		if ( ! property_exists( $xlinkAttributes, 'arcrole' ) )
		{
			$this->reportMissingArcAttribute( '3.5.3.9.4', 'arcrole', $linkbase );
			$result = false;
		}

		if ( ! property_exists( $xlinkAttributes, 'to' ) )
		{
			$this->reportMissingArcAttribute( '3.5.3.9.3', 'to', $linkbase );
			$result = false;
		}

		if ( ! property_exists( $xlinkAttributes, 'from' ) )
		{
			$this->reportMissingArcAttribute( '3.5.3.9.2', 'from', $linkbase );
			$result = false;
		}

		return true;
	}