Fox News has announced that it is parting ways with Tucker Carlson, its far-right prime-time host, and will air "Fox News Tonight" as an interim show helmed by rotating personalities until a new host is named. Carlson was a top-rated host for the network, drawing 334,000 viewers in the coveted 25- to 54-year-old demographic in the 8 p.m. slot for the week ended April 20. Fox Corporation shares dropped after the news was released.