Over the moon
Definition 1 of 1
Pro Tip 1/3Emotional Intensity
Used to express a very high level of happiness, like a feeling of being on cloud nine. 
She was over the moon when her daughter was born.
Pro Tip 2/3Positive News
Often used in response to positive news or events that greatly satisfy someone. 
They were over the moon about the surprise birthday party.
Pro Tip 3/3Colloquial Use
It's informal, so it's more suitable for conversations with friends than formal settings. 
He was over the moon with his new bicycle!