Fox dominated the primetime ratings wars on Thursday, as both ”American Idol” and ”Bones” grew week to week. NBC’s ”The Office,” meanwhile, held up well in its first post-Steve Carell seg, tying with ABC’s ”Grey’s Anatomy” as the No. 1 scripted show among young adults.

According to preliminary nationals from Nielsen, ”American Idol” averaged a 6.1 rating/20 share in adults 18-49 and 20.8 million viewers overall in the 8 o’clock hour, impressively beating the combined demo delivery of ABC, CBS and NBC; it grew nearly 10% week to week. And up even more at 9 o’clock was ”Bones” (3.3/9 in 18-49, 11.1 million viewers overall), ranking first or second in most key categories.

At NBC, ”Community” was low kicking off the night (1.4/5 in 18-49, 3.5 million viewers overall), and following a special repeat of ”The Office” at 8:30 (1.1/3 in 18-49, 2.7 million viewers overall), the first original episode of ”The Office” without Steve Carell averaged a hearty 3.5 rating/10 share in adults 18-49 and 6.8 million viewers overall , edging out both ABC and Fox to win the 9 o’clock half-hour in 18-49. From there, ”Parks and Recreation” (2.6/7 in 18-49, 5.1 million viewers overall) and ”30 Rock” (2.1/6 in 18-49, 4.2 million viewers overall) were both up vs. last week when they started later than usual. And closing out the night was ”Outsourced” (1.5/4 in 18-49, 3.1 million viewers overall), which finished well behind dramas on CBS and ABC.

The Alphabet net started slowly with ”Wipeout” (1.4/5 in 18-49, 4.8 million viewers overall), whose novelty wore off weeks ago. ”Grey’s Anatomy” followed with a winning performance in demos for the 9 o’clock hour (3.5/10 in 18-49, 9.9 million viewers overall), down slightly week to week. And at 10, ”Private Practice” (2.3/6 in 18-49, 6.9 million viewers overall) was up a tick week to week to place second.

CBS ran second in the night’s opening hour with ”The Big Bang Theory” (3.1/11 in 18-49, 10.3 million viewers overall) and ”Rules of Engagement” (2.2/7 in 18-49, 7.7 million viewers overall), both down a bit vs. last week. At 9, ”CSI” (2.2/6 in 18-49, 10.5 million viewers overall) continues to droop opposite strong crime-drama competition from Fox’s ”Bones,” but ”The Mentalist” was a winner for the net in the 10 o’clock hour (2.6/7 in 18-49, 13.6 million viewers overall).

At CW, ”The Vampire Diaries” (1.2/4 in 18-49, 2.7 million viewers overall) was flat week to week, and ”Nikita” (0.8/2 in 18-49, 1.9 million viewers overall) was up, especially among women 18-34 (0.9/3 from 0.7/2).

Preliminary 18-49 averages for the night: Fox, 4.7/14; CBS, 2.5/7; ABC, 2.4/7; NBC, 2.0/6; Univision, 1.4/4; CW, 1.0/3.

In total viewers: Fox, 12.8 million; CBS, 11.0 million; ABC, 7.2 million; NBC, 4.2 million; Univision, 3.4 million; CW, 2.1 million.