The families of three Americans being held in Iran after straying across the border say new video shows they were on a harmless vacation.Shane Bauer, Sarah Shourd and Josh Fattal have been detained since July 31.They apparently crossed into Iran by accident while hiking in a scenic area in northern Iraq.The video was shot by a fourth American on the trip who didn't go hiking because he was ill.Bauer's mother, Cindy Hickey, lives in eastern Minnesota.She says the video makes it obvious they were on vacation and not meaning to do harm.