Razelikh's Defilement Question

So, the description on this reads:

"Soul Cleave reduces the remaining cooldown on a random Sigil by 8 sec or Elysian Decree by 2 sec."

Is there a priority to this? If both Sigil of Flame and Elysian Decree are on cooldown, and it procs, is it random as to which one gets the reduction? Is it Elysian Decree if it is on CD, and another sigil if not? Is it both Elysian Decree and another sigil?

Some clarification would be great - thanks!