[noun] + でもあり、[noun] + でもある [na-adj] + でもあり、[na-adj] + でもある [i-adj 〜い → 〜く] + もあり、[i-adj 〜い → 〜く] + もある
AでもありBでもある says one thing is A and is just as much B: two roles, or two qualities that seem not to fit together. でもあり and でもある go straight after a noun or a な-adjective.
The も on both halves gives them equal weight: neither is the main one. With であり on the first half, A is what the subject is first of all, and B is added to it.
These go beyond a pair of nouns.
Every item but the last takes でもあり.
An い-adjective changes its い to く and takes もあり and もある.
The pattern belongs to writing and formal speech. The polite ending is でもあります, and in conversation いしゃ医者でもあるし、さっか作家でもある says the same.