Astrology basics

Detriment

Detriment is the sign opposite a planet's domicile, where it operates under strain — Mars is in detriment in Libra, a sign ruled by Venus, whose character runs opposite to Mars's.

It doesn't mean the planet "doesn't work" — rather that its natural way of expressing itself runs against the grain of the sign's character, which can create inner tension but also unusual, interesting compromises.