How long can you have a BIXI for?

I'm curious about the duration of a BIXI rental. Can you tell me how long can one keep a BIXI bike for? Is there a specific time limit or is it more flexible depending on the user's needs? I'd like to know if I can rent a BIXI for a few hours or if I can keep it for an entire day or even longer. Is there a fee associated with extended rentals, and if so, how is it calculated? I'm eager to understand the rental policies and options available for BIXI bikes to make the most of my experience.