IdolMaster has had at least 4 anime series, movies, arcade games, mobile games, music cds, and regular concerts. It's a big property for them. Miura used to play idol games when he took his breaks from Berserk, but not sure if he played IdolMaster or Love Live, the other big Idol property.

Might just hear less of it because it is not as exposed to the western market as their other properties.