Segment Reporting Operating Activity Within Reportable Segments (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Segment Reporting Information [Line Items]
Operating income (loss)	$ 20,407	$ 21,441	$ 19,373	$ 19,880	$ 20,247	$ 18,206	$ 16,641	$ 16,812	$ 81,101	$ 71,906	$ 56,343
Gross Profit									165,071	149,352	125,906
Total Retail
Segment Reporting Information [Line Items]
Property revenue									93,449	91,991	86,511
Property expense									(23,900)	(24,955)	(24,512)
Operating income (loss)									69,549	67,036	61,999
Total Office
Segment Reporting Information [Line Items]
Property revenue									90,527	78,101	57,319
Property expense									(26,688)	(23,780)	(18,015)
Operating income (loss)									63,839	54,321	39,304
Total Multifamily
Segment Reporting Information [Line Items]
Property revenue									16,125	14,852	14,321
Property expense									(5,917)	(5,914)	(5,578)
Operating income (loss)									10,208	8,938	8,743
Total Mixed-Use
Segment Reporting Information [Line Items]
Property revenue									54,956	50,522	44,634
Property expense									(33,481)	(31,465)	(28,774)
Operating income (loss)									$ 21,475	$ 19,057	$ 15,860