Case Closed was taken off most likely because Funimation, I believe, stopped dubbing episodes. Adult Swim probably didn't feel like looping the series over and over again since Funimation wasn't going to produce anything new
Case Closed as of now has 12 full seasons of 472 episodes, but Funimation stopped dubbing at season 4 around episode 50. Even if you watch the official Funimation channel, all they do is play the show up until the end of the 4th season and then loop back to episode 1 and start all over again =\
I'd like to see Case Closed on Adult Swim again, but not until Funimation picks the series back up with new episodes, because you can't watch a Case Closed episode a second time unless you completely forget what happens, it's no fun watching the episode and knowing what's going to happen
Wiki says 83 episodes were dubbed. D:
Anyway, I find it funny how it's better than the myriad of Law and Orders.