How can I join all data of two raster datasets in ArcMap 10.2?

[JuliaKamp]

I have two raster datasets in ArcMap10.2. One is displaying rails and one that is displaying a 100m Buffer to both sides of it. My cellsize is 100x100m. What I want is to combine the rails AND the Buffer around it in one raster. All tools that I used only display the overlapping rasters in the new raster dataset, but I want to have ALL data in the new raster.

I tried Multiply and Plus in the raster calculator. I tried 'Mosaic To New Raster'. I tried merge... Actually I tried all possible union, combine, merge, join etc functions that I know about in ArcGIS. Either they just don´t work or I don´t get the result that I want.

Does anyone know how I can join the two rasters to have all data in the new layer?

[JuliaKamp · Accepted solution]

Finally it worked with the 'Mosaic To New Raster' tool. I used MAXIMUM as Mosaic Operator. I have no idea why it works now, suddenly, and did not work when I tried it earlier. But now I have my layer and that´s important ^^.