In Spatial Analyst, Input Raster + 0 is basically the same as copying the raster.
This is still not working for me.
I have set the extent of the raster layer to that of a larger one; have the display the NoData turned on via the Layer Properties dialog. It shows an extended area, but when I try to generate a new raster with the maximum values from the small raster and correct size raster via CellStatistics, the result raster has the extent of my small raster and not of the larger one, which is what I need.
I have also experimented with the Con and IsNull tools, but no luck in expanding the small raster to the extent of the larger one.
I found an easy way to do this:
Actually, since my posting, I found out that it wasn't as simple as "Et voila" because of what I believe is a bug in ArcMap 10.3. For some rasters, the Export Raster Data dialog changes the extent that was set manually to the data frame (by zooming in ArcMap). In my case, it only considered about half the height of the data frame extent! My workaround: zoom far out enough and then export the raster.
After enlarging the raster beyond the extent that I needed (with NoData cells), I have tried to clip it back to a smaller area that I needed, but ArcMap had a problem there too. This data being mainly intermediary for my CellStatistics calculations, it wasn't too much of a problem.
I hope this helps.