Summary of Significant Accounting Policies (Details)	3 Months Ended
Mar. 31, 2017
Minimum [Member]
Revenue Recognition [Abstract]
Period of cancellation notice	10 days
Maximum [Member]
Revenue Recognition [Abstract]
Period of cancellation notice	30 days

The amount of time required to cancel or terminate the contract with the entity.

No definition available.

Name:	prft_PeriodOfCancellationNotice
Namespace Prefix:	prft_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration