How to auto-size WIDTH of text box?

Hello all. I am familiar with the auto-size feature for textboxes, but that doesn't help me with my issue as it only auto-sizes height (unless I'm doing something wrong). I need the textbox to autosize to width ONLY. I do not want my text to wrap to the next line. Right now, I am manually selecting the two right anchors of the text box and adjusting them pixel by pixel to get it at the perfect size. There has to be a better way! For example, in Excel, when you double click a column divider it will autosize the column to the largest line of text in that column. I'm looking for a similar function in Illustrator for textboxes. Hope this makes sense!