No insurance borrowed my car and the rear end, my insurance cover?

I let my friend take my car to drop to his friend and he ended up getting backed into a truck and severely damaged my rear bumper. Because it was on private property, the police could do nothing but watch us to share information. My friend had no insurance, but my car is insured. Will my insurance can cover my damage, even though I was not here? This accident was the fault of the truckers, because he argued in my car, but this guy does not even have an identity, but the car was his family and said it is safe.

I worked for Allstate and State Farm in California, I can only advice in my state, it can be different in another, and it depends on the company you have. I worked for both companies so they will most likely cover. But excluded some pilots and cover only persons named on the policy. It is best to call your health insurance if it covers anyone driving a car. You can also file a claim with the insurance to other parties, if known. Call the insurance company and tell them what happened. Even if you still need to know if your insurance covers all driving.