  We give a one-to-one correspondence between ideals in the Steinberg algebra
of a Hausdorff ample groupoid $G$, and certain families of ideals in the group
algebras of isotropy groups in $G$. This generalises a known ideal
correspondence theorem for Steinberg algebras of strongly effective groupoids.
We use this to give a complete graph-theoretic description of the ideal lattice
of Leavitt path algebras over arbitrary commutative rings, generalising the
classification of ideals in Leavitt path algebras over fields.
