Last Updated Jan 18, 2016 9:37 AM EST
A Twitter post showed the first glimpse of the Washington Post's Jason Rezaian shaking hands with Brett McGurk of the State Department who led the release negotiations.
Rezaian was jailed a year and a half ago, charged with spying.
Speaking from Landstuhl, Germany, Rezaian's brother, Ali Rezaian, told "CBS This Morning" on Monday that he spoke to his brother and he is "really happy to be out."
"He really seems very positive, strong," Ali Rezaian said. "He wants to come out of this stronger than before and come back."
Ali Rezaian said the ordeal was all the more difficult because his brother was so public about his love for Iran.
"He has no qualms with the Iranian people," he said. "The way he's been treated by parts of the Iranian government is really criminal."
Pastor Saeed Abedini was detained in 2012, alleged to have organized underground Christian worship in Iran. Amir Hekmati, a former U.S. Marine, was arrested in 2011 while visiting his grandmother -- and charged with espionage.
As soon as the news broke, Hekmati's sister Sarah was on her way to meet him.
"I'm in a fog," she told CBS News' Adriana Diaz at Detroit's airport. "This is like surreal. I'm still in disbelief and honestly everything just happened so quickly that I don't think it'll hit me until I'm hugging him."
And she's all set to help him make up for lost time.
"Every new year, there's like a year-end review magazine, and I would save it so that he could get caught up," Sarah said.
On board, Sarah and her husband were only hours away from a reunion they feared would never come.
All three Americans were released from Tehran's infamous Evin prison after 14 months of top-secret bargaining that started on the sidelines of the nuclear talks.
Also free are Bahram Mechanic and Khosrow Afghahi, two of the seven prisoners the U.S. released from its jails as part of the swap. All were accused of violating American sanctions against Iran.
Finally, there's a mystery man, the fourth American prisoner who was released along with the others but apparently stayed behind in Iran. All we know is his name: Nosratollah Khosravi-Roosari.
The three Americans now in Germany spent their first night of freedom at the Landstuhl military hospital, which has long offered a warm welcome and medical care to U.S. hostages and prisoners on their way home.