NEW YORK — 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.

With a full season of "American Idol" to go, it's likely no one will eclipse Fox before the season ends in May.

The powerful talent competition had just under 30 million viewers for its Tuesday edition last week, and the Wednesday show had 24.8 million. No other show even reached 15 million. ABC's "Lost" was the most-watched scripted series.

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, Fox averaged 11.5 million viewers (6.7 rating, 11 share), NBC had 8.9 million (5.5, 9), CBS 8.1 million (5.2, 8), ABC 7 million (4.4, 7), the CW 2.2 million (1.5, 2), My Network TV 1.2 million (0.8, 1) and ION Television 540,000 (0.4, 1).

Among the Spanish-language networks, Univision led with a 3.4 million average (1.7, 3), Telemundo had 1.1 million (0.6, 1), TeleFutura 790,000 (0.4, 1) and Azteca 110,000 (0.1, 0).

ABC's "World News" narrowly won the evening news ratings race, averaging 9.44 million viewers (6.4 rating, 12 share). NBC's "Nightly News" had 9.41 million (6.3, 12) and the "CBS Evening News" 7 million (4.8, 9).

A ratings point represents 1,128,000 households, or one percent of the nation's estimated 112.8 million TV homes. The share is the percentage of in-use televisions tuned to a given show.

For the week of February 11-17, the top 10 shows, their networks and viewerships: "American Idol" (Tuesday), Fox, 29.96 million; "American Idol" (Wednesday), Fox, 24.75 million; "The Moment of Truth," Fox, 14 million; "Lost," ABC, 13.76 million; "Extreme Makeover: Home Edition," ABC, 13.49 million; "Survivor: Micronesia," CBS, 13.18 million, "Deal or No Deal" (Monday), NBC, 13.15 million; Movie: "Knight Rider," NBC, 12.72 million; "60 Minutes," CBS, 12.5 million; "Deal or No Deal" (Thursday), NBC, 12.18 million.