I like to expand my suggestion for working with InDesign library files. One library created in InDesign CC, one library created in CC 2014. As already mentioned, you can have both libraries open in both versions. Drag and drop the objects you want to copy/paste to the appropriate library and drag them out to your page in whatever InDesign version you currently working:
The little lock icon at the bottom of the library will indicate that you cannot add items. But you can use the assets stored in the library.
Left: InDesign CC
Right: InDesign CC 2014
Of course opening a CC file in CC 2014 is possible and copy/paste from that. But you cannot open a CC 2014 file in CC. You first have to save a IDML file and open that in CC. Working with two libraries will be easier when you permanently like to exchange assets in both directions.
Uwe