Share ''A que sí''

I'm not sure this is an idiom, but it's a little phrase that you hear over and over again. It's used as a tag at the end of a sentence when you want to say 'isn't that so?' In English, this can often be expressed as one of a number of tags, like,'don't you, haven't you, won't you, etc. So you might hear: 'Quieres ir al café, ¿a que sí?' which would be 'you want to go to the café, don´t you?' ...