U.S. equity futures are firmly in the red, as investors pull back from all-time highs ahead of details on a major tax overhaul from Republican lawmakers.
 
The House Ways and Means Committee is set to release the initial tax reform bill on Thursday, a day after missing a self-imposed deadline. Trump has said he wants passage of the legislation around Christmas.
 
Investors so far have seen little detail on highly anticipated reform, though the promise of what's to come has supported market gains in recent months. The Trump White House has promised tax cuts for individuals and businesses, but details on how they will be paid for without blowing up the deficit have not been forthcoming.