Operating Partnership Earnings Per Share - Schedule of Computation of Basic and Diluted Net Income Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net income	$ 20,190	$ 156,435	$ 59,826	$ 218,679
Noncontrolling interests - consolidated real estate entities		(22,416)		(22,554)
Preferred unit distributions	(922)	(922)	(2,766)	(2,766)
Unvested restricted stock (allocation of earnings)	(47)	(314)	(133)	(435)
Net income available to common shareholders, adjusted	$ 19,178	$ 132,470	$ 56,801	$ 192,460
Weighted average units outstanding - basic	54,326	54,301	54,409	54,233
Dilutive units from stock options	16	72	16	103
Weighted average units outstanding - diluted	54,342	54,373	54,425	54,336
Basic	$ 0.35	$ 2.44	$ 1.04	$ 3.55
Diluted	$ 0.35	$ 2.44	$ 1.04	$ 3.54
Post Apartment Homes, L.P. [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net income	$ 20,190	$ 156,435	$ 59,826	$ 218,679
Noncontrolling interests - consolidated real estate entities		(22,416)		(22,554)
Preferred unit distributions	(922)	(922)	(2,766)	(2,766)
Unvested restricted stock (allocation of earnings)	(47)	(314)	(133)	(435)
Net income available to common shareholders, adjusted	$ 19,221	$ 132,783	$ 56,927	$ 192,924
Weighted average units outstanding - basic	54,447	54,431	54,530	54,366
Dilutive units from stock options	16	72	16	103
Weighted average units outstanding - diluted	54,463	54,503	54,546	54,469
Basic	$ 0.35	$ 2.44	$ 1.04	$ 3.55
Diluted	$ 0.35	$ 2.44	$ 1.04	$ 3.54