The 49-year-old Australian actress talked about her marriage to Urban in the July issue of InStyle.
"Keith and I don't ever text. We call. That's just what we've always done. We're old-school," she told the magazine.
Kidman and Urban married in 2006, and have since welcomed daughters Sunday and Faith. The actress said in the interview that a perfect day for her involves spending time at home with her family.
"On weekends, we just hang -- wake up, get the paper. We eat together as a family, breakfast and dinner always," she shared. "We're very, very tight. It's how I was raised. It's what I know."
Kidman's emphasis on family may come as no surprise given her self-professed maternal instinct.
"I suppose the basis of who I am is maternal. I'm the oldest child in my family, which probably has a lot to do with nurturing and taking care of people. So, yeah, a lot of my forces are maternal," she said.
"I mean, they're romantic too. I've always chosen to have really deep, intense romantic relationships," the star added. "I don't dabble. That's who I am, and my mother's always said it: 'You're just a child who attaches.'"
Kidman was previously wed to Tom Cruise from 1990 to 2001. She and Urban looked the picture perfect couple at the 2017 Academy of Country Music Awards in April, where Urban performed his song "The Fighter," which was inspired by Kidman.
"I remember when he first played it for me, and I started to cry because ... he writes these things -- they come out of, I don't know -- and they're like beautiful gifts," the actress said on the red carpet.