  When bilayer graphene is rotationally faulted to an angle $\theta\approx
1.1^\circ$, theory predicts the formation of a flat electronic band and
correlated insulating, superconducting, and ferromagnetic states have all been
observed at partial band filling. The proximity of superconductivity to
correlated insulators has suggested a close relationship between these states,
reminiscent of the cuprates where superconductivity arises by doping a Mott
insulator. Here, we show that superconductivity can appear without correlated
insulating states. While both superconductivity and correlated insulating
behavior are strongest near the flat band condition, superconductivity survives
to larger detuning of the angle. Our observations are consistent with a
"competing phases" picture, in which insulators and superconductivity arise
from disparate mechanisms.
