Goodwill

The carrying value of goodwill and the activity for the two year period ending December 31, 2017 are as follows (in thousands):



Balance, December 31, 2015	$	596,316
Goodwill from acquisitions	220,795
Currency translation adjustments	(15,705		)
Balance, December 31, 2016	801,406
Goodwill from acquisitions	96,431
Classification as asset held for sale	(13,090		)
Currency translation adjustments	25,064
Balance, December 31, 2017	$	909,811

During the year ended December 31, 2017, the Company recorded $96.4 million of goodwill primarily in connection with the purchase price allocation associated with Prox Dynamics, AS ("Prox Dynamics").

The Company reviews its goodwill for impairment annually during the third quarter, or more frequently, if events or circumstances indicate that the carrying value of a reporting unit exceeds its fair value. During the third quarter of 2017, the Company completed its annual review of goodwill and determined that no impairment of its recorded goodwill was necessary. During the fourth quarter of 2017, the Company allocated goodwill totaling approximately $13.1 million to assets held for sale related to the planned divestiture of the Consumer and Small and Medium-Sized (SMB) portion of the Security business. See Note 18, "Business Acquisitions and Divestitures," for further discussion. As a result of the reallocation of goodwill to the disposal group, the Company assessed whether there were any potential triggers or indicators of impairment on the retained portion of the Security segment. The Company concluded there had been no significant changes in the reporting unit assessment that would result in a significant change to the future expected cash flows generated from the retained asset groups. As such, as of December 31, 2017, the Company concluded that goodwill was not impaired.