As of both June 30, 2021 and December 31, 2020, goodwill was $51.9 million. We have selected June 30 as our annual goodwill impairment testing date. We performed a qualitative analysis of the fair value of our goodwill and determined there was no impairment as of June 30, 2021. As of June 30, 2021 and December 31, 2020, there were no indicators of impairment.

In connection with our marketing initiatives, we have purchased the naming rights to the downtown Oklahoma City arena that is home to the Oklahoma City Thunder National Basketball Association franchise. Under the terms of the naming rights agreement, we have committed to make estimated payments escalating annually from $4.0 million to $6.1 million through 2035. Upon the conclusion of the initial term, the agreement may be extended upon the mutual agreement of both parties for an additional five-year period. The cost of the naming rights has been recorded as an intangible asset with an offsetting liability as of the date of the contract. The intangible asset is being amortized over the life of the agreement on a straight line basis commencing in June 2021. The offsetting liability is being relieved through sales and marketing expense using the effective interest method over the life of the agreement.

All of our intangible assets other than goodwill are considered to have definite lives and, as such, are subject to amortization. The following table presents the components of intangible assets within our consolidated balance sheets:

	June 30, 2021
	Weighted Average Remaining				Accumulated
	Useful Life		Gross		Amortization			Net
	(Years)
Intangibles:
Naming rights		15.4	$	60,199	$	(325	)	$	59,874
Trade name		1.0		3,194		(2,981	)		213
Total			$	63,393	$	(3,306	)	$	60,087

	December 31, 2020
	Weighted Average Remaining			Accumulated
	Useful Life	Gross		Amortization			Net
	(Years)
Intangibles:
Trade name	1.5	$	3,194	$	(2,875	)	$	319
Total		$	3,194	$	(2,875	)	$	319

Amortization of intangible assets for the three and six months ended June 30, 2021 was $0.4 million and $0.4 million, respectively. Amortization of intangible assets for the three and six months ended June 30, 2020 was less than $0.1 million and $0.1 million, respectively. We estimate the aggregate amortization expense will be $2.1 million for the remainder of 2021, $4.0 million for 2022, and $3.9 million for 2023, 2024, 2025 and 2026, respectively.