Former Fox News Channel anchor Gretchen Carlson has settled her sexual harassment lawsuit against Roger Ailes, the case that led to the downfall of Fox's chief executive with stunning swiftness this summer.

In a statement Tuesday, Fox parent company 21st Century said that "we regret and apologize for the fact that Gretchen was not treated with the respect and dignity that she and all of our colleagues deserve."

"We sincerely regret and apologize for the fact that Gretchen was not treated with the respect and dignity that she and all of our colleagues deserve," the media company said in a statement.

It is unclear how much Ailes himself might pay but Fox News, part of 21st Century Fox, essentially insures Ailes against any settlement, the magazine said, citing two people familiar with the arrangement.

Carlson has voluntarily dismissed her federal lawsuit in New Jersey against Ailes, a court filing shows.

Carlson was paid $20 million, according to someone familiar with the confidential settlement who spoke under condition of anonymity.

Carlson alleged that she was demoted and let go from Fox after she refused Ailes' sexual advances and complained about workplace harassment. Ailes denied the charges, but 21st Century launched an investigation and Ailes resigned after other women made allegations.