Is do a double take an idiom?

Is do a double take an idiom? to react with surprise; to have to look twice to make sure that one really saw correctly. When the boy led a goat into the park, everyone did a double take. When the nurse saw that the man had six toes, she did a double take.

to react with surprise; to have to look twice to make sure that one really saw correctly. When the boy led a goat into the park, everyone did a double take. When the nurse saw that the man had six toes, she did a double take.