Theorem on Injective Dimension in Weibel's "An Introduction to Homological Algebra"

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This fact is stated in Weibel's book without proof:

If $A$ is a finitely generated module over a commutative Noetherian local ring $(R,\mathfrak{m},k)$, then $id(A) \le d$ is equivalent to $\operatorname{Ext}^{n}_{R}(k,A)=0$ for all $n > d$.

I can prove one direction since $id(A) \le d$ is equivalent to $\operatorname{Ext}^{n}_{R}(R/\mathfrak{a},A)=0$ for all $n > d$ for all ideals $\mathfrak{a} \subset R$. Could you help me with the other direction?