ride high - Phrases/Idioms
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Enjoy success, as in He's been riding high ever since they made him vice-president. The high here alludes to both elevated and elated status. [First half of 1800s]