Buying Skyrim Legendary Edition while already having Skyrim

Hello guys I want to buy Skyrim Legendary Edition because it will be cheaper than buying all the DLCs. But I already have Skyrim. What would happen if I buy Legendary Edition that including Skyrim. Will there be any problem or Steam add me only those DLC's ? [Sorry for English :D]

Steam considers Skyrim and Skyrim: Legendary Edition to be separate games. You won't be able to gift or trade the Skyrim base game, but you can purchase it and you'll have two Skyrim games in your Steam Library. I've done this several times for Deluxe/GOTY editions as well.

Edit: You can tell steam considers them to be separate games because they exist separately in the store. (Search for Skyrim and you'll see what I mean.)