With $8.5 million on the opening day and $17 million estimated for the four days holiday, "solid" would be the right world.
However, it could be tagged as "very good" considering the competition (not speaking about all the controversy and circumstances).
Indeed, it had to compete with not less than Jennifer Aniston and Brad Pitt (both setting records for the highest one-day total ever for a film opening on Christmas with $14.8 million ($28 million on four days) and $11.8 million ($21 million on four days) respectively), as well as one of my favorite actor, Adam Sandler, who came third with a one day earning of $10.5 million (and eventually winner of the estimated four days holiday with $33 million).
All the other films opening on the holiday came fairly far from these four.
With very good users reviews and the Christmas season past, it may eventually fare even beter.