Continue rolling back pep-3141 changes that changed behavior from 2.5. This
round included:
 * Revert round to its 2.6 behavior (half away from 0).
 * Because round, floor, and ceil always return float again, it's no
   longer necessary to have them delegate to __xxx___, so I've ripped
   that out of their implementations and the Real ABC. This also helps
   in implementing types that work in both 2.6 and 3.0: you return int
   from the __xxx__ methods, and let it get enabled by the version
   upgrade.
 * Make pow(-1, .5) raise a ValueError again.
diff --git a/Doc/library/math.rst b/Doc/library/math.rst
index 8c9f0f8..6c78104 100644
--- a/Doc/library/math.rst
+++ b/Doc/library/math.rst
@@ -26,9 +26,8 @@
 
 .. function:: ceil(x)
 
-   Return the ceiling of *x* as a float, the smallest integer value greater than
-   or equal to *x*. If *x* is not a float, delegates to ``x.__ceil__()``, which
-   should return an :class:`Integral` value.
+   Return the ceiling of *x* as a float, the smallest integer value greater than or
+   equal to *x*.
 
 
 .. function:: copysign(x, y)
@@ -46,9 +45,8 @@
 
 .. function:: floor(x)
 
-   Return the floor of *x* as a float, the largest integer value less than or
-   equal to *x*. If *x* is not a float, delegates to ``x.__floor__()``, which
-   should return an :class:`Integral` value.
+   Return the floor of *x* as a float, the largest integer value less than or equal
+   to *x*.
 
 
 .. function:: fmod(x, y)