Difference between "nationally" and "regionally" accredited online universities

What is the difference between the two? Someone from St. Leo University told me their college is nationally accredited which is better than the college I am thinking about: Ashworth. With Ashworth, the program is self-paced; not accelerated like most others. That’s why it appeals to me.

Ashworth College is accredited by the Distance Education and Training Council, which is recognized as an authorized national accrediting body by the Department of Education and the Council for Higher Education Accreditation. It’s strictly an online school.

St. Leo University is accredited by the Southern Association of Colleges and Schools, which is also recognized as an authorized national accrediting body by the DOE and the Council for Higher Education Accreditation. It’s a physical university (the campus is in Florida) that also offers distance learning programs.

There’s no real difference between the accreditation of the two schools. It’s just that the Southern Association is the official accrediting body for colleges in the southeast, and the Distance Education and Training Council is the official accrediting body for online schools.