http://www.apple.com/macbook-pro/specs gives 7 hours of WiFi use and 30 days standby on a 95 Wh battery for a MacBook pro. So, it will be somewhere between 0.1-ish W and 13-ish W for idle state. I cannot find something better. For the Mac Mini, http://support.apple.com/kb/HT3468 gives 11W in idle.
FWIW I consistently get 11-13w at idle, 7 hours battery under use from my Samsung Series 7 Chronos i7. Obviously Samsung takes cues from Apple but I'm pleased at half the price.