Connecticut shot 61 percent from the floor, while holding Idaho to 14 baskets on 53 attempts (26 percent).
UConn outrebounded Idaho 45-23, and outscored the Vandals in the paint 46-8.
"We had a great experience with what top-of-the-nation basketball looks like," said Idaho forward Alyssa Charlston. "That gives us something to look at next season and going into the summer. We need to look at that. Coach was talking about how hard we need to go every single play and UConn does that every single play."
UConn played the game without one of its key post players. Freshman Breanna Stewart injured her left calf in practice on Friday, and sat out as a precaution. She is expected to be ready to play on Monday.
The Huskies are trying for a record sixth consecutive trip to the Final Four and an eighth national championship. They have won 30 games for an NCAA record eighth straight season.
The 30th win came on coach Geno Auriemma's 59th birthday. The Huskies are 8-1 when playing on that day, the lone loss coming to North Carolina State in the 1998 regional final.
UConn is a top seed for the seventh straight year. The Huskies are 21-2 in first-round games, which doesn't include the two seasons they received first-round byes.
They came in having won their last six first-round games by an average of 41 points.
The win was the 86th for the Huskies in the NCAA tournament, second only to Tennessee's 112.
Idaho, which was making only the third trip to the East Coast in program history, also lost in the first round in 1985, 74-51 to Cheryl Miller and Southern California.
This year's team lost nine of their first 20 games, but finished strong, winning 14 of their final 20, and swept through the Western Athletic Conference tournament.
"This is just the first step for us and our program and where we want to be," said Newlee. "UConn started somewhere. Just like we are now."