Group similar to Urantia, but with longer book

I recall finding out online once about a group with beliefs which seemed to me to be very similar to those of the Urantia people. But this group’s book was even bigger.

Anyone have any idea what group it is I might have stumbled on? I’ve forgotten.

-FrL-

Urantia Book

For those of us who never heard of it before.

Like me, fr’instance.