LM311 maximum voltage question

I wish to use an LM311 comparator with 25.2 volts on a single rail. (I'm self taught in what little electronics I know, so apologies if I misuse terms) Max voltage is listed on the data sheet as 18 volts. However, it's keyed to the following: "All voltage values, unless otherwise noted, are with respect to the midpoint between VCC+ and VCC-". If I am using a single rail power source, it seems to me that VCC- in my case would be zero volts, making the midpoint 12.6 volts. 18 volts over the midpoint would be 30.6 volts, placing my intended voltage well within limits. Am I correct?