Goodwill and Other Intangible Assets

9 Months Ended

Sep. 30, 2023

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill and other intangible assets consisted of the following (amounts in thousands):


	At September 30, 2023						At December 31, 2022
	Gross Book Value		Accumulated Amortization		Net Book Value		Gross Book Value		Accumulated Amortization		Net Book Value
Goodwill	$	165,843	$	—	$	165,843	$	165,843	$	—	$	165,843
Shurgard® Trade Name	18,824		—		18,824		18,824		—		18,824
Finite-lived intangible assets, subject to amortization	981,254		(751,630)		229,624		758,106		(710,256)		47,850
Total goodwill and other intangible assets	$	1,165,921	$	(751,630)	$	414,291	$	942,773	$	(710,256)	$	232,517

Finite-lived intangible assets consist primarily of acquired customers in place. Amortization expense related to intangible assets subject to amortization was $16.0 million and $41.4 million for the three and nine months ended September 30, 2023, respectively, and $20.0 million and $78.2 million for the same periods in 2022. During the nine months ended September 30, 2023, intangibles increased $223.1 million, in connection with the Simply Acquisition (Note 3) and the acquisition of real estate facilities (Note 4).

The estimated future amortization expense for our finite-lived intangible assets at September 30, 2023 is as follows (amounts in thousands):


Year	Amount
Remainder of 2023	$	39,491
2024	108,871
2025	56,693
2026	18,013
2027	2,687
Thereafter	3,869
Total	$	229,624