Odd Hairy Bee Thing

I suspect this is some type of hairy bee and not a fly. Though I don't have a positive identification and just taking a guess. You can see the proboscis going into the yellow Starthistle.
If you can help identify this hairy critter, please leave a comment.

On a side note, the yellow Starthistle is classified as "Noxious Weed" in Idaho. It can be bad news for horse if they eat it. The Starthistle can cause "chewing disease", which can lead to permanent brain damage and die from dehydration and starvation.