It’s very close to Detroit, in what they call the Detroit metro area, but you’re right, it’s not Detroit proper.
It’s not “Detroit proper” at all ...I live in MI 15...it runs from the Ohio State line north and includes only part of Detroit.
http://www.govtrack.us/congress/findyourreps.xpd?state=MI&district=15
I’m glad to see Dingell is struggling...but this headline paints a VERY inaccurate picture