Reconciliation of Financial Instruments Remeasured on Recurring Basis (Detail) (USD $)	3 Months Ended								3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2012 Contingent Consideration Related to Business Combinations		Mar. 31, 2013 Contingent Consideration Related to Business Combinations		Dec. 31, 2012 Contingent Consideration Related to Business Combinations		Mar. 31, 2013 Derivative Instruments Related to Business Combinations		Mar. 31, 2012 Derivative Instruments Related to Business Combinations		Mar. 31, 2013 Other Assets Related to Business Combinations		Mar. 31, 2012 Other Assets Related to Business Combinations
Financial Instruments Measured At Fair Value On Recurring Basis [Line Items]
Beginning balance													$ 992,000	[1]
Total gains:
Included in earnings	16,000	(174,000)												[1]		[2]
Included in earnings									246,000	[3]	462,000	[4]
Purchases, issuances, or settlements													(162,000)	[1]	772,000	[2]
Ending balance		772,000											830,000	[1]	772,000	[2]
Beginning balance			(1,613,000)	[5]	(1,787,000)	[6]	(1,787,000)	[6]	(274,000)	[3]	(3,050,000)	[4]
Purchases, issuances, or settlements			1,613,000	[5]					28,000	[3]	266,000	[4]
Ending balance					$ (1,787,000)	[6]	$ (1,787,000)	[6]			$ (2,322,000)	[4]

[1] The change of $162,000 for other assets related to business combinations during the three months ended March 31, 2013 is comprised of payments received on the master lease assets.

[2] The change of $772,000 for other assets related to business combinations during the three months ended March 31, 2012 is comprised of the recognition of a master lease asset of $772,000 related to the acquisition of the Promenade Corporate Center property (see Note 3).

[3] The change of $274,000 for derivative instruments related to business combinations during the three months ended March 31, 2013 is related to changes to the redemption provision for OP units issued in connection with the 2011 Edwards Theatres acquisition as a result of (a) a decrease of $246,000 due to recognition of a gain included in earnings related to changes in the fair value of the redemption obligation and (b) a decrease of $28,000 due to the redemption of corresponding OP units.

[4] The change of $728,000 for derivative instruments related to business combinations during the three months ended March 31, 2012 is related to changes to the redemption provision for OP units issued in connection with the 2011 Edwards Theatres acquisition as a result of (a) a decrease of $462,000 due to recognition of a gain included in earnings related to changes in the fair value of the redemption obligation and (b) a decrease of $266,000 due to the redemption of corresponding OP units.

[5] The change of $1.6 million for contingent consideration related to business combinations during the three months ended March 31, 2012 is comprised of a decrease in the obligation due to the payment of approximately $1.6 million in earn-outs in January 2012.

[6] There was no change in the contingent consideration related to business combinations during the three months ended March 31, 2013, with the earn-out periods related to the two applicable acquisitions ending on June 30, 2013 and September 30, 2013, respectively.