1. A voice recognition apparatus which performs recognition of voice to be outputted from an output unit, the voice recognition apparatus comprising: a processor configured to control: first, second and third voice recognizers which each recognize an input voice and obtain a recognition result including a candidate character string corresponding to the input voice, each of said first, second and third voice recognizers include a memory that stores a dictionary; and a controller which, when it is decided based on said recognition result obtained by each of said first and second voice recognizers to cause said third voice recognizer to recognize said input voice, causes said third voice recognizer to recognize said input voice by using the dictionary included in said third voice recognizer including said candidate character string obtained by at least one of said first and second voice recognizers, and causes said output unit to output said recognition result obtained by said third voice recognizer, wherein the recognition results obtained by each of said first and second voice recognizers further include score values indicating accuracy of said candidate character strings, and whether or not to cause the third voice recognizer to recognize said input voice is decided based on an index including at least one of said score values which are obtained by said first and second voice recognizers and are a maximum, a similarity indicating a degree that said candidate character strings obtained by said first and second voice recognizers match each other, and an order distance indicating a degree of difference in an order of said candidate character strings aligned in order of said score values obtained by said first and second voice recognizers.