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		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net income	$ 19,651	$ 47,991	$ 39,636	$ 62,244
Noncontrolling interests - consolidated real estate entities	0	(154)	0	(138)
Preferred unit distributions	(922)	(922)	(1,844)	(1,844)
Unvested restricted stock (allocation of earnings)	(46)	(110)	(86)	(132)
Net income available to common shareholders, adjusted	$ 18,642	$ 46,687	$ 37,623	$ 59,979
Weighted average units outstanding - basic	54,455	54,223	54,452	54,199
Dilutive units from stock options	14	112	15	115
Weighted average units outstanding - diluted	54,469	54,335	54,467	54,314
Basic	$ 0.34	$ 0.86	$ 0.69	$ 1.11
Diluted	$ 0.34	$ 0.86	$ 0.69	$ 1.10
Post Apartment Homes, L.P. [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net income	$ 19,651	$ 47,991	$ 39,636	$ 62,244
Noncontrolling interests - consolidated real estate entities	0	(154)	0	(138)
Preferred unit distributions	(922)	(922)	(1,844)	(1,844)
Unvested restricted stock (allocation of earnings)	(46)	(110)	(86)	(132)
Net income available to common shareholders, adjusted	$ 18,683	$ 46,805	$ 37,706	$ 60,130
Weighted average units outstanding - basic	54,576	54,358	54,573	54,334
Dilutive units from stock options	14	112	15	115
Weighted average units outstanding - diluted	54,590	54,470	54,588	54,449
Basic	$ 0.34	$ 0.86	$ 0.69	$ 1.11
Diluted	$ 0.34	$ 0.86	$ 0.69	$ 1.10