Extensive Background Check from Kaiser Permanente?

I just recently got a contingent job offer from Kaiser. I first have to take a drug test and background check (ran by LexisNexis) I heard that these background checks are very, very, extensive and they take a lot of time looking into every detail. I have 3 years of nursing experience, prior to this, I worked retail jobs here and there maybe 5-6 years ago. I honestly don't have the W-2 or paystubs from those retail jobs. Do you think this background check might actually ask for it? Even if it is unrelated to the job I am being considered for? How would I provide proof if they want it?
LexisNexis is a vast, pervasive legal information collecting company that mines public information from police reports and courts about arrests and convictions, and sells it to anybody that wants to pay for it, rather than having to check 100's of databases, themselves. If you have a criminal background, they'll find it. If you get a DUI, as an example, and don't notify your auto insurance carrier, LN does it for them, automatically- that way the carrier doesn't have to run a background check on you every time you renew a policy. LN doesn't look for employment history. If you need to verify an old job, the Social Security Administration has records of every job you've ever had, if it was above board.

Hi Vincere....it's been a while since your post, but just wondering if you got the job with Kaiser? Take care!