You will need to be careful about your tax status as some benefits such as provided housing and home-leave airfare would be taxible (in whole or in part) by the US.

Take care on what your package includes. Even though rental prices for apartments and villas have slipped some in recent months, they are VERY expensive by US standards. Expect to pay at least QR 12 -15,000 a month (at least $3-4,000) for a relatively modest furnished apartment in a good area (considerably more for a more than modest place to live).

Beyond housing, cost of living is not markedly higher than US (some things less, some more). Some things may, however, be hard to find here or quite expensive. Restaurant prices, outside of the hotels, are generally modest. Alcohol available in hotel bars (expensive) and at a single liquor shop for wich you need to get a liquor license. No pork.

Without family, you may find life here somewhat lonely. There are things to do, but you need to search for them.

As to the environment, you will not have any issue being an American. There are certainly enough of us here and, worst case, you can always pretend you are a Canadian (LOL). English is more widely spoken than Arabic.