Stock-Based Compensation Plans - Summary of Activity Related to Company's Restricted Stock (Parenthetical) (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Total value of the restricted share grants	$ 4,663	$ 3,038	$ 3,743

Share based compensation arrangement by share based payment award equity instruments other than options granted in period fair value.

No definition available.

Name:	pps_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantedInPeriodFairValue
Namespace Prefix:	pps_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration