It was a typical week in prime-time television -- "American Idol" dominated everything -- but Fox may have another reason for remembering it fondly: The network moved past CBS into first place for the TV season for average number of viewers, according to Nielsen Media Research.

For years Fox was regarded as fourth behind the Big Three of CBS, NBC and ABC. Now it's America's most popular TV network.

CBS premiered the broadcast network version of Showtime's "Dexter" on Sunday to a decent 8.2 million viewers. The series about a serial killer has been the subject of protests for being too disturbing for broadcast.

For the week of Feb. 11-17, network averages were: Fox, 11.5 million viewers (6.7 rating, 11 share); NBC, 8.9 million (5.5, 9); CBS, 8.1 million (5.2, 8); ABC, 7 million (4.4, 7); CW, 2.2 million (1.5, 2); My Network, 1.2 million (0.8, 1); ION, 540,000 (0.4, 1).

ASSOCIATED PRESS

1 American Idol (Tuesday) (Fox)

2 American Idol (Wednesday) (Fox)

3 The Moment of Truth (Fox)

4 Lost (ABC)

5 Extreme Makeover: Home Edition (ABC)

6 Survivor: Micronesia (CBS)

7 Deal or No Deal (Monday) (NBC)

8 Sunday Movie "Knight Rider" (NBC)

9 60 Minutes (CBS)

10 Deal or No Deal (Thursday) (NBC)

11 Two and a Half Men (CBS)

12 Daytona 500 Post Race (Fox)

13 NCIS (CBS)

14 Deal or No Deal (Wednesday) (NBC)

15 CSI: Crime Scene Investigation (CBS)

16 Law & Order (NBC)

17 The New Adventures of Old Christine (CBS)

18 Without a Trace (CBS)

19 Cold Case (CBS)

20 Dance War: Bruno vs. Carrie Ann (ABC)