How common is common?

Use of individual English idioms varies from culture to culture and geographically.

Google News is an excellent method of determining how frequently an idiom is being used.

It is possible to discover how common an English idiom is by checking the volume and frequency of usage. 

In essence - how much are people using a particular English idiom in their everyday lives.

Another excellent method to check how common an idiom is by using a "corpora".

A corpora allows variations on the search as well as filtering by region.

An easy to use corpora can be found here ... http://corpus.byu.edu/glowbe/