David Lyle, a TV veteran who championed unscripted TV and headed National Geographic Channels and Fox Reality Channel, died Thursday at his home in Los Angeles after a long battle with cancer. He was 67.

After working in TV in Australia and in London, Lyle came to Los Angeles in 2001 as head of FremantleMedia North America where he helped launch “American Idol” on Fox. He most recently served as president of Pact US, an advocacy org for unscripted TV producers.

Earlier this year, Lyle helped steer the merger of Pact US with the rival Nonfiction Producers Association, creating NPACT. The organization reps most of the largest unscripted TV production companies.

“David Lyle was one of the few television executives who thrived on both a creative and business level,” said Howard T. Owens, co-CEO of Propagate Content, who worked with Lyle at Nat Geo. “He was one of the kindest, most fun, and caring people I’ve ever known. He always had time to mentor people and help others out in their careers.”

A native of Sydney, Lyle was a lively presence with a hearty laugh. He brought great competitive zeal to his work and didn’t shy away from taking on provocative industry issues in public forums. Last year, he penned a column for Variety addressing the conflicts that independent producers were facing amid the growth of cable programming giants.

“David Lyle was a rare breed, in our industry and in the world. A true bon vivant, he brought light and life into every room, along with a passion for the creatives of this business,” said John Ford, general manager of NPACT. “We will all miss David’s maverick mettle, along with his vitality, brilliant insights and humor.”

Lyle worked as a geologist and as a high school chemistry teacher in Australia before breaking into television as a writer and producer for Australia’s ABC and Ten networks. By the late 1980s, he was working at Nine network as an executive producer and program creator. He advance to head of development and acquisitions for Nine, where he worked on local renditions of such popular formats as “Who Wants to Be a Millionaire” and “Trading Spaces.”

Lyle moved from Australia to Pearson Television in the U.K. to serve as head of worldwide development and acquisitions. That post led him to relocate in 2001 to Los Angeles, where he served as president of entertainment for FremantleMedia North America until 2004. During that period, the unit worked with Simon Fuller’s 19 Entertainment to turn Fox’s “American Idol” into the most-watched series in primetime.

After Fremantle, Lyle was recruited by Fox to launch an international sales venture for the company’s reality TV formats. But he quickly shifted to launching the Fox Reality Channel cabler in 2005. He had a five-year run at the helm of the channel, which was profitable but ultimately had a hard time gaining widespread distribution. It was transformed into Nat Geo Wild in early 2010.

Fox Reality was known for its embrace of raunchy fare including “My Bare Lady,” “Battle of the Bods” and “Seducing City.” Lyle was unabashed in defending the channel’s programming.

After Fox Reality shuttered, Lyle became head of National Geographic Channels, a joint venture of Fox and the National Geographic Society. He ran the group from 2011 through 2014 and launched such franchises as “Wicked Tuna” and “Life Below Zero” and helped boost the group’s earnings. But some of the programs Lyle backed were seen as too far afield from Nat Geo’s mission. He was succeeded in 2014 by marketing chief Courteney Monroe.

Lyle was a natural choice to launch the Pact US organization, an offshoot of the U.K.’s powerful Producers Alliance for Cinema and Television, in 2015. He was well-known and well-regarded by many of the biggest names in unscripted TV. In 2000, he was also among the co-founders of the Format Recognition and Protection Association, which aims to protect producers against unauthorized copying of proprietary TV formats.

“David was a champion for the underdog creators, a passionate advocate for formats and a true believer who inspired countless producers, format creators and channels the world over,” said producer Phil Gurin, who is co-chairman of FRAPA. “He was a dear friend, confidante, raconteur and legend. He shall be missed here, there and everywhere — especially at the bar at the Carlton Hotel with a dram in his hand, a smile on his face and a story in his heart.”

Lyle’s survivors include his wife, Janne, and three children.