Note that both Parallel.For and Parallel.ForEach return an instance of ParallelLoopResult, which can be used to determine if a parallel loop has completed execution.

Nested foreach loops are the method I use to iterate through each element in an array, but in this case they don't help me. Any ideas? The script as it stands is below: ...

In the line above, the @ symbol tells PowerShell that we are creating an array. The key to understanding how ForEach loops work in PowerShell is to understand what the variables do.