WooCommerce - Add Bcc email to Completed Order Email

/**
* @Title: WooCommerce - Add Bcc email to Completed Order Email
* @Author: Mina Pansuriya
* @Blog URL: http://minapansuriya.com/woocommerce-add-bcc-email-to-completed-order-email/
**/

add_filter( 'woocommerce_email_headers', 'es_headers_filter_function', 10, 3);

function es_headers_filter_function( $headers, $id, $object ) 
{
	if ($id == 'customer_completed_order')
	{
		$headers .= 'BCC: '.$id.' <manager@gmail.com>' . "\r\n";
	}
  return $headers;
}