7. Goodwill and Other Intangible Assets, net

The financial statements reflect goodwill from previous acquisitions that is all attributable to the Permian Basin business segment and reporting unit.

Changes in the carrying amount of goodwill were as follows:


	Permian Basin
Balance at January 1, 2019	$	34,180
Acquisition of Superior		6,858
Balance at December 31, 2019		41,038
Changes in Goodwill		-
Balance at March 31, 2020	$	41,038

As a result of the global COVID-19 pandemic and the recent decrease in demand and oversupply of oil and natural gas during the first quarter of 2020 which impacted the trading price of our common stock, we identified a trigger event requiring us to assess our long-lived and intangibles assets for recoverability and perform a quantitative impairment assessment of reporting units with goodwill, all of which is within the Permian Basin reporting unit.

To determine the fair value of our reporting units and test for impairment, we utilized an income approach (discounted cash flow method), as we believe this is the most direct approach to incorporate the specific economic attributes and risk profiles of our reporting units into our valuation model. We did not utilize a market approach given the current situation with the industry and the lack of contemporaneous transactions. To the extent market indicators of fair value were available, we considered such information as well as market participant assumptions in our discounted cash flow analysis and determination of fair value. The discounted cash flow methodology is based, to a large extent, on assumptions about future events, which includes the use of significant unobservable inputs, representative of a Level 3 fair value measurement. Given the current volatile market environment, we utilized third-party valuation advisors to assist us with these valuations. These analyses required significant judgment, including management’s short-term and long-term forecast of operating performance, revenue growth rates, profitability margins, capital expenditures, timing of future cash flows based on an eventual recovery of the oil and gas industry, the remaining useful life and service potential of the asset (in the case of long-lived assets, including definite-lived intangibles), and discount rates (in the case of our goodwill assessment) based on our weighted average cost of capital. These forecasted cash flows took into consideration historical and recent results, committed contracts and near-term prospects and management's outlook for the future, as well as the increased market risk surrounding the award and execution of future contracts.

Based on our quantitative assessments, we determined the carrying value of our long-lived assets was recoverable and goodwill associated with our Permian Basin reporting unit was not impaired. However, the fair value of the reporting unit exceeded its net book value by a margin of less than 20%. Our estimate of fair value was based upon assumptions believed to be reasonable. However, impairment assessments incorporate inherent uncertainties, including projected commodity pricing, supply and demand for our services and future market conditions, which are difficult to predict in volatile economic environments and could result in impairment charges in future periods if actual results materially differ from the estimated assumptions utilized in our forecasts. Further, given the dynamic nature of the COVID-19 pandemic and related market conditions, we cannot reasonably estimate the period of time that these events will persist or the full extent of the impact they will have on our business. We will continue to take actions designed to mitigate the adverse effects of the rapidly changing market environment and expect to continue to adjust our cost structure to market conditions. This may include continued reductions of our workforce to better align our employee count with anticipated lower activity levels and sustained reduction of capital spending at maintenance levels until demand returns to previous levels.

Intangible assets other than goodwill at the dates indicated below consisted of the following:

Intangible assets other than goodwill at the dates indicated below consisted of the following: Intangible assets other than goodwill at the dates indicated below consisted of the following:
	March 31, 2020
	Weighted	Gross
	average	Carrying		Accumulated		Net Book
	remaining lives	Amount		Amortization		Value
Intangible assets subject to amortization
Customer relationships	8.1	$	132,720	$	(35,001)	$	97,719
Total			132,720		(35,001)		97,719
Indefinite lived assets:
Tradenames			16,400		—		16,400
Total intangible assets other than goodwill		$	149,120	$	(35,001)	$	114,119


	December 31, 2019
	Weighted	Gross
	average	Carrying		Accumulated		Net Book
	remaining lives	Amount		Amortization		Value
Intangible assets subject to amortization
Customer relationships	8.3	$	132,720	$	(31,254)	$	101,466
Total			132,720		(31,254)		101,466
Indefinite lived assets:
Tradenames			16,400		—		16,400
Total intangible assets other than goodwill		$	149,120	$	(31,254)	$	117,866

The aggregate amortization expense for intangible assets subject to amortization was $3.7 million and $3.5 million for the three months ended March 31, 2020 and 2019, respectively, and is included in other depreciation and amortization in the consolidated statements of comprehensive income (loss).

The estimated aggregate amortization expense as of March 31, 2020 for each of the next five years and thereafter is as follows:


Rest of 2020	$	10,909
2021		14,656
2022		13,302
2023		12,881
2024		12,881
Thereafter		33,090
Total	$	97,719