3. Acquired Intangible Assets and Liabilities

Summarized below are the carrying values for the major classes of intangible assets and liabilities (unaudited and in thousands):


		March 31, 2019						December 31, 2018
		Gross						Gross
		Carrying		Accumulated		Net Carrying		Carrying		Accumulated		Net Carrying
	Useful Lives	Value		Amortization		Value		Value		Amortization		Value
Customer Relationships	1 to 12 years	$	95,705	$	(30,449)	$	65,256	$	95,705	$	(28,461)	$	67,244
In-Place Leases	0.5 to 10 years		32,066		(18,701)		13,365		32,066		(17,670)		14,396
Solar Power Agreement (1)	17 years		13,747		(3,841)		9,906		13,747		(3,639)		10,108
Platform Intangible	3 years		—		—		—		9,600		(9,600)		—
Acquired Favorable Leases
Acquired below market leases - as Lessee	46 years		2,301		(8)		2,293		2,301		—		2,301
Acquired above market leases - as Lessor	0.5 to 8 years		4,649		(3,416)		1,233		4,649		(3,247)		1,402
Tradenames	3 years		—		—		—		3,100		(3,100)		—
Total Intangible Assets		$	148,468	$	(56,415)	$	92,053	$	161,168	$	(65,717)	$	95,451

Solar Power Agreement (1)	17 years		13,747		(3,841)		9,906		13,747		(3,639)		10,108
Acquired Unfavorable Leases
Acquired below market leases - as Lessor	3 to 4 years		809		(671)		138		809		(611)		198
Acquired above market leases - as Lessee	11 to 12 years		2,453		(821)		1,632		2,453		(767)		1,686
Total Intangible Liabilities (2)		$	17,009	$	(5,333)	$	11,676	$	17,009	$	(5,017)	$	11,992

(1)

Amortization related to the Solar Power Agreement asset and liability is recorded at the same rate and therefore has no net impact on the statement of operations.

(2)

Intangible liabilities are included within the “Advance rents, security deposits and other liabilities” line item of the consolidated balance sheets.

Above or below market leases are amortized as a reduction to or increase in rental revenue in the case of the Company as lessor as well as a reduction to or increase in rent expense in the case of the Company as lessee over the remaining lease terms. The net effect of amortization of acquired above‑market and below‑market leases resulted in a net decrease in rental revenue of $0.1 million and $0.1 million for the three months ended March 31, 2019 and 2018, respectively. The estimated amortization of acquired favorable and unfavorable leases for each of the five succeeding fiscal years ending December 31 is as follows (unaudited and in thousands):


	Net Rental Revenue		Net Rental Expense
	Decrease		Increase/(Decrease)
2019 (April - December)	$	368	$	(121)
2020		647		(166)
2021		46		(166)
2022		17		(166)
2023		17		(166)
Thereafter		—		1,446
Total	$	1,095	$	661

Net amortization of all other identified intangible assets and liabilities was $3.1 million and $4.0 million for the three months ended March 31, 2019 and 2018, respectively. The estimated net amortization of all other identified intangible assets and liabilities for each of the five succeeding fiscal years ending December 31 is as follows (unaudited and in thousands):


2019 (April - December)	$	8,946
2020		11,379
2021		10,137
2022		9,910
2023		9,910
Thereafter		28,339
Total	$	78,621