6. Goodwill and Identifiable Intangible Assets, Net

Goodwill

The changes in the carrying amount of goodwill are as follows (in thousands):

  ​ ​ ​

Mechanical Segment

  ​ ​ ​

Electrical Segment

  ​ ​ ​

Total

Balance at December 31, 2023

$

393,276

$

273,558

$

666,834

Acquisitions and purchase price adjustments (See Note 5)

 

208,236

200

208,436

Balance at December 31, 2024

601,512

273,758

875,270

Acquisitions and purchase price adjustments (See Note 5)

52,897

97,348

150,245

Balance at December 31, 2025

$

654,409

$

371,106

$

1,025,515

The aggregate goodwill balance as of December 31, 2025 and 2024 includes $116.6 million of accumulated impairment charges, all of which relate to the mechanical segment.

During our annual impairment testing on October 1, 2025, we performed a quantitative assessment where the fair value of each reporting unit was estimated using a discounted cash flow model combined with a market valuation approach. We assigned a weighting of 50% to the discounted cash flow analysis and 50% to the public company approach for the year ended December 31, 2025. Based on this assessment, we concluded that the fair value of each of the reporting units was greater than its carrying value. A 10% decline in the estimated fair value of each reporting unit due to a change in assumptions would not have resulted in us recording an impairment in 2025.

For the years ended December 31, 2025, 2024 and 2023, no impairment of our goodwill or other intangible assets was recorded.

There are significant inherent uncertainties and management judgment involved in estimating the fair value of each reporting unit. While we believe we have made reasonable estimates and assumptions to estimate the fair value of our reporting units, it is possible that a material change could occur. If actual results are not consistent with our current estimates and assumptions, or the current economic outlook worsens, goodwill impairment charges may be recorded in future periods.

Identifiable Intangible Assets, Net

Identifiable intangible assets consist of the following (dollars in thousands):

Weighted-Average

December 31, 2025

December 31, 2024

  ​ ​ ​

Remaining Useful Lives

  ​ ​ ​

Gross Book

  ​ ​ ​

Accumulated

  ​ ​ ​

Gross Book

  ​ ​ ​

Accumulated

  ​ ​ ​

in Years

  ​ ​ ​

Value

  ​ ​ ​

Amortization

  ​ ​ ​

Value

  ​ ​ ​

Amortization

Customer Relationships

 

6.8

$

636,734

$

(294,683)

$

550,518

$

(241,263)

Backlog

 

1.4

 

24,148

(10,300)

 

54,918

 

(40,328)

Trade Names

 

17.8

 

177,746

(48,477)

 

151,561

 

(40,989)

Total

$

838,628

$

(353,460)

$

756,997

$

(322,580)

Identifiable intangible assets attributable to businesses acquired in 2025 have been preliminarily valued at $130.3 million, consisting of customer relationships, trade names and backlog. Identifiable intangible assets attributable to businesses acquired in 2024 have been valued at $251.3 million, consisting of customer relationships, trade names and backlog. The weighted-average initial amortization period for the identifiable intangible assets attributable to businesses acquired in 2025 and 2024 was 10.5 years and 9.1 years, respectively.

The amounts attributable to customer relationships and trade names are amortized to “Selling, General and Administrative Expenses” based upon the estimated consumption of their economic benefits, or under a shorter period of time using the straight-line method if the pattern of economic benefit cannot be reliably estimated. Our intangible assets related to customer relationships and trade names are amortized over periods from one to twenty-five years. The amounts attributable to backlog are amortized to “Cost of Services” on a proportionate method over the remaining backlog period. Amortization expense for the years ended December 31, 2025, 2024 and 2023 was $79.6 million, $97.3 million and $43.4 million respectively.

As of December 31, 2025, future amortization expense of identifiable intangible assets was as follows (in thousands):

Year ending December 31—

  ​ ​ ​

  ​ ​ ​

2026

$

76,564

2027

 

65,826

2028

 

63,119

2029

56,852

2030

44,317

Thereafter

 

178,490

Total

$

485,168

Historical Timeline

Fiscal YearFiled
2025Feb 19, 2026Showing above
2024Feb 20, 2025
2023Feb 22, 2024
2022Feb 22, 2023
2021Feb 23, 2022
2020Feb 25, 2021
2019Feb 26, 2020
2018Feb 21, 2019
2017Feb 22, 2018
2016Feb 23, 2017
2015Feb 23, 2016

About Goodwill & Intangibles Disclosures

Goodwill and intangible asset disclosures reveal the premium paid in acquisitions and how management assesses whether that premium retains its value. Since goodwill is no longer amortized under US GAAP, the annual impairment test is the only mechanism that adjusts carrying values downward — making the assumptions behind that test critically important for investors.

Key signals: a history of goodwill impairments suggests management consistently overpays for acquisitions. Watch the gap between reporting unit fair value and carrying amount — when fair value exceeds carrying amount by less than 10-20%, a small decline in business performance could trigger a write-down. For finite-lived intangibles, examine useful life assumptions across customer relationships, technology, and trade names; aggressive estimates inflate near-term earnings. Compare total intangibles-to-total-assets ratios against peers to assess acquisition dependency. Rising goodwill as a percentage of equity can signal balance sheet fragility.