Verizon wants complete control of its joint Verizon Wireless division with Vodafone, so it is reportedly considering a merger of the two companies or a buyout. Vodafone currently holds a 45 percent stake in the wireless venture, estimated to be worth about $115 billion. The two have discussed a merger as recently as December, according to published reports. The talks came to a standstill when neither side could agree on leadership details, such as a location for company headquarters. A Verizon buyout of Vodafone’s stake remains an option.