Two flavors. (1) "Above-the-fray, impartial" — common in
超然的立场 (impartial position),
超然物外 (above worldly matters). (2) "Transcendent, otherworldly" — has a Daoist/Buddhist tinge, suggesting the calm of someone unattached to worldly gain. The
然 ending = "-ly / -ish," same family as
自然,
突然,
索然.