Removes one or more instances from the specified Auto Scaling group.
After the instances are detached, you can manage them independently from the rest of the Auto Scaling group.
If you do not specify the option to decrement the desired capacity, Auto Scaling launches instances to replace the ones that are detached.
If there is a Classic load balancer attached to the Auto Scaling group, the instances are deregistered from the load balancer. If there are target groups attached to the Auto Scaling group, the instances are deregistered from the target groups.
For more information, see Detach EC2 Instances from Your Auto Scaling Group (http://docs.aws.amazon.com/AutoScaling/latest/DeveloperGuide/detach-instance-asg.html) in the Auto Scaling User Guide.