Customer custom value not saving to customer_enitity table

I have created new column in customer_entity table

class UpgradeData implements UpgradeDataInterface{

    public function upgrade(ModuleDataSetupInterface $setup, ModuleContextInterface $context)
    {
        if (version_compare($context->getVersion(),'1.0.6'<0)){

            $customerName = $setup->getTable('customer_entity');

            if ($setup->getConnection()->isTableExists($customerName) == true) {

                $connection = $setup->getConnection();

                $connection->addColumn(
                    $customerName,
                    'family_name',
                    [
                        'type' => MagentoFrameworkDBDdlTable::TYPE_TEXT,
                        'length' => 100,
                        'nullable' => true,
                        'comment' => 'Family Name'
                    ]
                );
            }
        }
}

and i am creating a customer programmatically.

$customerFactory = $this->_objectManager->get('MagentoCustomerModelCustomerFactory');
$newCustomer = $customerFactory->create(); 
$newCustomer->setWebsiteId($this->_storeManager->getWebsite()->getId());
$newCustomer->setEmail('email@email.com');
$newCustomer->setFirstname('First name');
$newCustomer->setLastname('Last name');
$newCustomer->setPassword('Password');
.....
$newCustomer->setData('family_name', $externalUser['FamilyName']);
$newCustomer->save();

But only family_name (custom field) is not storing in customer_entity table.

Is this the proper way to store custom field ?

$newCustomer->setData('family_name', $externalUser['FamilyName']);

any idea?