Keith Urban said in Nashville this weekend he enjoys collaborating with other artists so he can see "what comes of those energies coming together."

During an interview Saturday at the CMA Music Festival at LP Field, Urban told The (Nashville) Tennessean he liked performing with "American Idol" runner-up Kree Harrison on the Grand Ole Opry stage last week because he could relate to where she is in her career.

"I think it just comes from being a guitar player," he said. "I just like working with people and seeing what comes of those energies coming together.

"That's why I like doing 'Idol,'" he said.

Urban said he wanted to hear Harrison sing on the Opry stage from the first time he heard her voice on "Idol."

He said he'd like the opportunity to perform alongside the Rolling Stones -- even over a trip to the moon.

"I'm sure the moon's great," Urban said. "But there's something pretty awesome about being 6 inches away from Keith Richards' face in an arena situation."