Detention and arrest are similar, yet drastically different situations.
Detention does not mean the kind of detention you received when you were in high school. This detention is when a police officer briefly holds and questions somebody. Think of a cop stopping you for a short period of time at a checkpoint so you can sober up or call someone to come and drive you home. You are not under arrest, but you cannot leave. In order to make an arrest from a detention, the officer would need probable cause that you have contributed to illegal activity. This can stem from their search of your vehicle and finding drug paraphernalia.
Only when a suspect is formally arrested, will the police officer read the Miranda Rights to him or her. This informs the defendant that they have the right to remain silent and the right to an attorney. These rights are meant to protect the defendant. The defendant will likely also have the right to bail, yet another right that serves in the interest of the defendant. Orange County Bail Bond Store can help you with this particular right.