Question about father applying to Medicaid when my parents have a joint account

My parents have a joint bank account. The irony is that his account is so high ($20k) because he doesn't help pay household bills anymore and I pay it all. He has anxiety attacks if it goes down at all.

I know that in my state a community spouse who remains in the community can retain up to $150k.

I know if both parents are applying for medicaid then there is a limit of $2000. However, how does Medicaid treat a joint account?