Remove key_size from EC keys docs
diff --git a/docs/hazmat/primitives/interfaces.rst b/docs/hazmat/primitives/interfaces.rst
index f4597fb..c5a430d 100644
--- a/docs/hazmat/primitives/interfaces.rst
+++ b/docs/hazmat/primitives/interfaces.rst
@@ -524,12 +524,6 @@
 
         The elliptic curve for this key.
 
-    .. attribute:: key_size
-
-        :type: int
-
-        The bit length of the curves base point.
-
     .. method:: public_key()
 
         :return: :class:`~cryptography.hazmat.primitives.interfaces.EllipticCurvePublicKey`
@@ -567,12 +561,6 @@
 
         The elliptic curve for this key.
 
-    .. attribute:: key_size
-
-        :type: int
-
-        The bit length of the curves base point.
-
 
 .. class:: AsymmetricSignatureContext