There are different levels of Elite Status on NW - Platinum being the highest on NW. When one is a platinum, they get an 125% mileage bonus, so a flight that is normally 11,000 miles is worth 24,750 miles overall, 11,000 of which will count towards the persons status for next year.

There's a 310.00 base on NW and it brings about 11,400+ miles (dca-dtw-ams-ist-ams-dtw-dca). Seems like a decent deal. But the above posts about appearance and fees is not good! My sister went to IST a few weeks ago and and had a great time and didn't have any issues.