Not only but also : complex or compound

I’ve read a sentence like this:

Not only did George buy the house, but he also remodeled it.

I think this counts as a complex sentence, but I want to get some extra opinions.  Doesn’t “Not only did George buy the house” modify “remodeled,” thus making the first clause dependent?  In common English usage, the position of the subject “George” after “did” is fine in an interrogative sentence, but it’s not in a declarative sentence.  Does the departure from standard declarative syntax suggest that the first clause is not independent (and therefore dependent)?