Deferred Revenue and Acquisition Related Liabilities, net

12 Months Ended

Dec. 31, 2012

Deferred Revenue [Abstract]

Deferred Revenue and Acquisition Related Liabilities, net

Deferred Revenue and Acquisition Related Liabilities, net

Deferred revenue and acquisition-related liabilities, net consisted of the following at December 31, 2012 and 2011:

	December 31,
	2012		2011
	(in thousands)
Deferred revenue related to tenant-funded tenant improvements	$	56,461	$	41,884
Other deferred revenue	2,314		1,310
Acquisition-related intangible liabilities, net (1)	59,129		36,587
Total	$	117,904	$	79,781

________________________

(1) See Note 4 for additional information.

Deferred Revenue Related to Tenant-funded Tenant Improvements

During the years ended December 31, 2012, 2011, and 2010, $9.1 million, $9.3 million, and $9.7 million, respectively, of deferred revenue related to tenant-funded tenant improvements (including discontinued operations) was amortized and recognized as rental income. The following is the estimated amortization of deferred revenue related to tenant-funded tenant improvements as of December 31, 2012 for the next five years and thereafter:

Year Ending	(in thousands)
2013	$	10,054
2014	9,339
2015	8,255
2016	7,825
2017	6,409
Thereafter	14,579
Total	$	56,461