U.S. Bank Pre-Employment Background Check

I recently was offered a "conditional offer of employment" this is pending a background check, drug test, etc. I just had a question regarding that because I worked for a different bank previously and was let go due to the current economy. How long does the background checks take, and what do they look at? Did they do the background check prior to the offer?

It takes about 1-2 weeks and they look for felons. what is on your record?

The background check only took a few days for me and they did it after the offer. What the real joke was is I had an arrest 5 years earlier, I was 18 and was arrested for being with my brother's young girlfriend(she was 13, 14) at the time and she stole a pair of underwear at the store i was at with her. Although I had no merchandise with me, the store claimed me responsible because she was a minor and felt "i knew about it". I was let out and the charges against me were later dropped. The court literally thought it was a joke. I've had other background checks with other places, worked in retail/banking for many years, and this never appears because I was never charged with this in the long run. Well US bank saw it, and needed a police report, upon going to the courthouse this isn't possible to obtain unless you are the store or person who filed charges. In the long run they withdrew from hiring me. So for everyone out there, they check for arrests.