"cool as a kite" - an idiom?

English as a Second Language English Vocabulary, Grammar and Idioms
1

Hi everybody,
do someone know the expression “cool as a kite”?
The whole phrase is:
Tom is here! He’s cool as a kite!

Thank you for helping me
Emma

2

.
There is an idiom “be as high as a kite”. Click this link:
high as a kite

There are a number of idioms with the word ‘cool’:
cool idioms

The expression “cool as a kite” is not an idiom or common expression.
It may simply mean “Tom is cool”:
thefreedictionary.com/cool
.

3

Thanks for your suggestion, Yankee!
Em