Acquired Intangible Assets and Liabilities

The following summarizes our acquired intangible assets (real estate intangibles, comprised of acquired in-place lease value, tenant relationship value and trade name along with acquired above-market lease value) and intangible liabilities (acquired below-market lease value) as of March 31, 2016 and December 31, 2015.



	Balance as of
(Amounts in thousands)	March 31, 2016			December 31, 2015
Real Estate Intangibles:
Acquired in-place lease value:
Gross amount	$	900,132		$	901,381
Accumulated amortization	(486,743		)	(472,933		)
Net	$	413,389		$	428,448
Tenant relationship value:
Gross amount	$	734,800		$	734,800
Accumulated amortization	(30,354		)	(14,495		)
Net	$	704,446		$	720,305
Trade name:
Gross amount	$	7,300		$	7,300
Accumulated amortization	(873		)	(417		)
Net	$	6,427		$	6,883
Acquired above-market leases:
Gross amount	$	121,455		$	122,311
Accumulated amortization	(91,348		)	(89,613		)
Net	$	30,107		$	32,698
Acquired below-market leases:
Gross amount	$	294,682		$	294,791
Accumulated amortization	(198,207		)	(193,677		)
Net	$	96,475		$	101,114

Amortization of acquired below-market leases, net of acquired above-market leases, resulted in an increase to rental revenues of $2.3 million and $2.3 million for the three months ended March 31, 2016 and 2015, respectively. The expected average remaining lives for acquired below-market leases and acquired above-market leases is 7.0 years and 4.4 years, respectively, as of March 31, 2016. Estimated annual amortization of acquired below-market leases, net of acquired above-market leases, for each of the five succeeding years and thereafter, commencing April 1, 2016 is as follows:



(Amounts in thousands)
Remainder of 2016	$	6,135
2017	6,947
2018	5,299
2019	5,338
2020	7,349
Thereafter	35,300
Total	$	66,368

Amortization of acquired in-place lease value (a component of depreciation and amortization expense) was $13.7 million and $11.6 million for the three months ended March 31, 2016 and 2015, respectively. The expected average amortization period for acquired in-place lease value is 8.2 years as of March 31, 2016. The weighted average remaining contractual life for acquired leases excluding renewals or extensions is 7.6 years as of March 31, 2016. Estimated annual amortization of acquired in-place lease value for each of the five succeeding years and thereafter, commencing April 1, 2016 is as follows:



(Amounts in thousands)
Remainder of 2016	$	39,423
2017	48,675
2018	46,469
2019	43,990
2020	39,951
Thereafter	194,881
Total	$	413,389

Amortization of tenant relationship value and trade names (a component of depreciation and amortization expense) was approximately $15.9 million and $0.5 million, respectively, for the three months ended March 31, 2016. The weighted average remaining contractual life for customer contracts and trade names is 11.1 years and 3.5 years, respectively. Estimated annual amortization of customer contracts and trade names for each of the five succeeding years and thereafter, commencing April 1, 2016 is as follows:



(Amounts in thousands)
Remainder of 2016	$	48,946
2017	65,261
2018	65,261
2019	64,844
2020	63,436
Thereafter	403,125
Total	$	710,873