Rooting at the top?

[Michael&Deanna]

Hello everyone. I bought my wife, Deanna, an orchid at Safeway (American grocery chain) for an anniversary a year and a half ago. The flowers lasted for months before dropping off, and, though it hasn't bloomed since, it appears very healthy. But it seems to be rooting from near the top of the plant now, and we're not sure what this means. Is it sign of a grafted plant? Is it normal? Should we cut the top portion free and root it as a separate plant? We would appreciate any advice you can give on this very much. I've searched online but cannot find anything on this. (see attached photo)