only too glad, ready, etc.

only too (something)

Very. Don't tell her the truth—she'd be only too glad to use it against you later. As a small business owner, I know only too well how tough it is to succeed in this economy.
Farlex Dictionary of Idioms.

only too ˈglad, ˈready, etc. (to do something)

very glad, ready, etc: If you want any advice, I’d be only too willing to give it. She was only too pleased to help.
Farlex Partner Idioms Dictionary
See also:
  • only too
  • only too (something)
  • only too pleased
  • only too well
  • be glad to see the back of (someone or something)
  • be glad to see the back of someone or something
  • be glad, etc. to see the back of somebody/something
  • (boy,) am I glad to see you!
  • Am I glad to see you!
  • so