I agree with Keep it Beefy. Cardio after lifting is fine so long as you keep it light. After about an hour of hard lifting you've depleted the glycogen in your muscles and start to burn fatty acids. Immediately after working out drink down your creatine and eat a carb loaded meal with lots of protein. Your insulin will spike (insulin is one of the most anabolic substances your body produces) as a result of the carbs. Your body is in its most anabolic state the first two hours after you finish working out, therefore, insulin+gear = good gains. I also recommend taking a cortisol inhibitor (cortistat) before working out as this will inhibit the cortisol produced by your body when you lift (cortisol is catabolic).
In a nutshell, cardio after working out is a great way to lose fat but still make muscle gains.
Emo, 6'4'' , 250 lbs