Can I use the latest iMac 27" (*not* the Retina one) as an external monitor for my MacBook Air 13"?

I just cannot get a straight answer from the Apple Store guys here. I own a 2014 Mac Book Air 13" and I would like to buy an iMac 27" 3.4Ghz 16 Gb 1To Fusion Drive to use it as both a home desktop as well as an external monitor for my MacBook Air. Some people say I cannot, some say I can. The "Target Display Mode (TDM) FAQ" (see Target Display Mode: Frequently Asked Questions (FAQ) - Apple Support) does not list the latest iMac 27" (2013 or 2014) but only seems to indicate TDM is not supported on the iMac 2014 27" Retina. Anybody bought an iMac 27" this year and tried to use it as a Display for their Mac Book Air? Thanks!