Idle temperatures are not important and will only show you that you have a problem if there is something grossly wrong with your cooling. You should run Prime95 for a few hours and then report the temperatures to see if you have a problem.
Is that good or bad? Because I"ve seen many people write they get temps in the 20's degrees Celsius zone using the evo
People get 20 degrees celsius zone with "perfect" conditions, realistically though, your lowest temps are going to be around the 30 zone on average. I have a Noctua NH-D14 (which I believe is better than the 212?) so I guess I would know?
You cannot go cooler than ambient room temps- if someone reports their CPU is at 20C, their room must be 20C (68F) or cooler for this to be true. My guess is there is an issue with what someone perceives their ambient room temp to be along with software that isn't reporting correct CPU temps. Both of these are cause to threads like this; 'I saw someone getting X degree temps, I am getting Y degree temps HELP!'.
Without using the same monitoring software you can't accurately identify what temperatures your cooler will allow at both idle and load.