be flying high idiom
平步青云；非常成功
If a person or a company is flying high, they are very successful.
The company was flying high as a maker of personal computers. 作为个人电脑的制造商，这家公司非常成功。
US informal异常兴奋（或高兴）
to be very excited or happy
When the winter Olympics came to Canada, the whole country was flying high. 当加拿大成为冬奥会的主办国时，整个国家都兴奋极了。