TV Ratings: 'American Idol' Premiere Brings 17.9 Million, Falls 19 Percent From Last Season

UPDATED: Losing less of its key demo than it did between 2011 and 2012, fast national returns give Wednesday's opener a 6.0 rating with adults 18-49.

American Idol returned Wednesday night, and fast national returns give the Fox singing competition's 12th-season premiere 17.9 million viewers and a 6.0 rating among adults 18-49 -- losses of roughly 19 percent from its January 2012 debut.

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Among total viewers, the veteran series took a bigger hit than it did between the previous two seasons, when it dropped 17 percent, but among adults 18-49, the dip wasn't as big as last season's (25 percent). The 2012 Idol opener brought 21.9 million viewers and a 7.4 rating.

However disappointing, given the big push to revamp the show, the numbers still leave American Idol safely ahead of any showing The Voice brought in the fall. It also gave Fox an easy win for the night by all measures, besting the rest of the Big Four's demo showings combined. History also tells us that Idol will recoup at least a tenth of a point when time-zone adjustments come in later Thursday.

The next test for Idol comes with the twice-a-week show's Thursday night premiere, which historically draws lower ratings. Last year's brought a 5.7 rating among adults 18-49 and 18 million viewers.

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Increased competition weighed slightly on other primetime broadcasts between 8 and 10 p.m. Thursday, though many series were in repeats.

ABC, which aired all originals, averaged a 2.5 rating among adults 18-49 and 7.5 million viewers. Its entire comedy block saw dips from the previous week, with The Middle (2.3 adults) starting the night down 4 percent. Neighbors (1.9 adults) dropped 9 percent, with Modern Family (4.3 adults) and Suburgatory (2.4 adults) dropping 10 and 8 percent, respectively. Nashville saw gains at 10 p.m., however, rising 5 percent to a 2.2 rating in the key demo. It was the show's best 18-49 rating since the series premiere.

An encore of NCIS led into Criminal Minds (2.8 adults) on CBS. The procedural was down 10 percent from its previous original in December. CSI (2.3 adults) won the hour and rose a tenth of a point from its most recent new outing. The network averaged a 2.1 rating with adults 18-49 and 10.7 million viewers.

NBC's entire Wednesday block was in repeats, giving the network a 0.8 rating with 18-49-ers and 2.9 million viewers.

On The CW, Arrow returned after more than a month off with a boost in adults 18-49. The series pulled a 1.1 rating in the demo, up a tenth of a point. Supernatural (0.9 adults) was steady with its most recent showing, giving the network an average 1.0 adults rating and 2.6 million viewers for the night.

Univision had a 1.6 rating with adults 18-49 and 3.9 million viewers.