What happens when someone is found not guilty by reason of insanity?

Henry McGowan has been found not guilty for the murder of his father by reason of insanity.  

 The jury accepted evidence that the 31-year-old was suffering from schizoaffective disorder when he killed his father at the Ballyfin Demesne hotel. But what happens when someone is found not guilty by reason of insanity? All to discuss with Trina O’Connor, Criminologist.