Ahmedabad-based Singhi & Co. concluded the demerger process for the Aditya Birla Group-owned telecom firm, Idea Cellular. The tower business of Idea Cellular is being demerged and will become part of a separate infrastructure company called Indus Towers. Indus Towers is a joint venture between Bharti Airtel, Vodafone Essar and Idea. Idea Cellular owns a 16 per cent stake in Indus Towers, while Bharti and Vodafone own 42 per cent each in the entity.