Year Ended December 31,
Year Ended December 31,
Year Ended December 31,
(In thousands)
2019
2018
2017
Asset impairment charges
$ 10,837
$ 58,166
$ 0
Goodwill impairment charge
$ 25,700
$ 13,466
$ 0
Impairment of long-term investments
$ 651
$ 15,487
$ 165,290
8 .
asset impairment charges .
asset impairment charges incurred during the year ended december 31 2019 were primarily the result of impairing the remaining nanthealth acquired customer relationship intangible balance of $ 8 .
1 million .
we also recognized non-cash impairment charges of $ 2 .
7 million on the retirement of certain hosting assets due to data center migrations .
impairment of long-term investments during the year ended december 31 2019 consisted of an impairment of $ 1 .
7 million associated with one of our long-term equity investments .
we also recovered $ 1 .
0 million from one of our long-term equity investments investment that we had previously impaired .
we also recorded a goodwill impairment charge of $ 25 .
7 million related to our hhs reporting unit .
refer to note 7 “ goodwill and intangible assets ” for further information regarding this impairment .
we incurred several non-cash asset impairment charges during the year ended december 31 2018 .
we recorded non-cash asset impairment charges of $ 33 .
2 million related to the write-off of capitalized software as a result of our decision to discontinue several software development projects .
we also recorded $ 22 .
9 million of non-cash asset impairment charges related to our acquisition of the patient / provider engagement solutions business from nanthealth in 2017 which included the write-downs of $ 2 .
2 million of acquired technology and $ 20 .
7 million representing the unamortized value assigned to the modification of our existing commercial agreement with nanthealth as we no longer expect to recover the value assigned to these assets .
the remaining $ 2 .
1 million of non-cash asset impairment charges recorded during the year ended december 31 2018 relate to the disposal of fixed assets as a result of relocating and consolidating business functions and locations from recent acquisitions .
we recorded a goodwill impairment charge of $ 13 .
5 million related to nanthealth during the year ended december 31 2018 .
refer to note 7 “ goodwill and intangible assets ” for further information regarding this impairment .
we recognized non-cash impairment charges of $ 15 .
5 million in 2018 related to two of our cost-method equity investments and a related note receivable .
these charges equaled the cost bases of the investments and the related note receivable prior to the impairment .
we recorded non-cash charges of $ 165 .
3 million during the year ended december 31 2017 including impairment charges of $ 144 .
6 million associated with two of the company ’ s long-term investments based on management ’ s assessment of the likelihood of near-term recovery of the investments ’ value .
the majority of the impairment charges related to our investment in nanthealth common stock .
we realized an additional $ 20 .
7 million loss upon the final disposition of the nanthealth common stock in connection with our acquisition of certain assets related to nanthealth ’ s provider / patient engagement solutions business .
refer to note 4 “ business combinations and other investments ” and note 14 “ accumulated other comprehensive loss ” for further information regarding these impairments .
the following table summarizes the non-cash asset impairment charges recorded during the periods indicated and where they appear in the corresponding consolidated statements of operations : .

Question: What caused the asset impairment charges in 2019?
Answer: primarily the result of impairing the remaining NantHealth acquired customer relationship intangible balance of $8.1 million.