The Id.au domains are for Australian individuals; due to this to be eligible for an id.au domain you must be ether an Australian citizen or an Australian resident, you cannot register an id.au domain for commercial purposes.
In addition to meeting one of the above eligibility requirements the domain name must be an exact match, abbreviation or acronym of the registrants personal name or otherwise closely and substantially connected to the registrant, because the domain name includes or in derived from one or more words of registrants personal name or is a name by which the registrant is commonly known by i.e. A nickname.