The 21-year-old Taylor powered down the runway on his fourth attempt and landed just shy of the 18 metre mark, leaping out of the sandpit and slapping his chest in delight at becoming the fifth best triple jumper of all time.
Briton Idowu was a strong favourite in the absence of the previous world leader Teddy Tamgho of France, who missed the championships after breaking his ankle, and had reinforced his position with an opening leap of 17.56 metres.
The flamboyant 32-year-old Olympic silver medallist then found third and fourth jumps of 17.70m and 17.77m, his best of the year, to look set for victory until Taylor's stunning leap.
"I did not expect to jump this far (but) I was definitely going for the win," the American said.
"It feels great to get the world title back to the U.S. It means the world to be here, on top of the world. Today was my day, but I will stay calm and keep working hard. This is a work in progress."
Idowu was unable to better the American's mark in his final two jumps and had to settle for silver ahead of Taylor's compatriot Will Claye, who won bronze with a leap of 17.50m.
"I wish I was happy but I'll take that medal," said Idowu. "I will go back home and work hard. I had no feelings at all during the competition, I focused on my competition and tried to move forward, jump further."
Idowu is one of Britain's brightest hopes of athletics' gold on home soil at the Olympics next year and the showman said he would be ready for the contest in his home city.
"I am looking forward to that," he said. "Today I tried to be on top, it was not for today but it will be next year."
Claye, a college team mate of Taylor at the University of Florida until both turned professional last month to prepare for the Olympics, was delighted.
"The result is great, bigger than me," he said. "I am very pleased and happy also for Christian's awesome jump."
Taylor said his new coach Rana Reider had played a major role in his improvement to world championship contender status.
"This breakthrough is due to a change of coach," he said. "He is very technical now, focused on speed and jump dynamics as a whole. When you have that and I have a strong faith in God, those things together. You really cannot lose."
Lysenko, who returned from a two-year ban for doping in 2009, threw 77.13 metres on her third attempt to take Heidler's world title.
German Heidler could manage only 76.06 to finish second and
"I think that after my suspension I came back stronger," said Lysenko. "Until the last attempt I wasn't sure I would get gold. My throws were very solid and stable but the hammer throw is an event in which you can never be sure about your victory until the last throws.
"This medal belongs to my coach. I waited so long for this medal, so I am very glad I was able to make myself ready for this competition."
Heidler moved into second place with her penultimate throw and had one last attempt to beat Lysenko's mark but released the hammer into the nets with a no-throw.
The German could not explain why she had failed to get it right on the night.
"I am not happy about this competition and my result. But at least I still got a silver medal because until the fifth attempt I was only third," Heidler told reporters.
"I do not know what was wrong with me today ... why I did not get it together ... there was just no rhythm."