How much can I expect to pay back in taxes for cashing out part of a 401K (roughly 20K), having already paid 20%in taxes and 10%penalty?

I cashed out part of my 401K (20K) after leaving my job this year. 20% was withheld for taxes, as well as a 10% penalty. My question is: After filing my tax return in 2017, is there an additional percentage in taxes I should expect to pay? Or will the 20% already withheld cover that?