Filtered Inside The Group

Table orders:

id	cust	amount	status
1	A	100	paid
2	A	50	refunded
3	B	200	paid
4	B	300	refunded
5	C	75	paid

SELECT cust, sum(amount) AS total
FROM orders
GROUP BY cust
HAVING sum(amount) FILTER (WHERE status = 'paid') >= 100;

What does this return?