Denzel Washington Good or Bad Acting

I'm watching this movie called Safe House with Denzel Washington and was discussing it with my brother. On one hand he does a great job at what he does. He always plays the same character, angry guy trying to keep it together. He does that role great. But what other range does he have? Does being considered a great actor mean he should be able to play more than one role or just one role great? I could change the character from Man on Fire to this one in Safe House and he is basically the same guy. So great actor or just average?