On February 14, 2018, the Company acquired 3VR. As a result of the acquisition, during the year ended December 31, 2018, the Company incurred restructuring and severance expenses of $0.6 million, consisting of facility rental related costs of $0.3 million, and severance related costs of $0.3 million. In the third quarter of 2018, the Company entered into an agreement with a tenant to sublease the 3VR office facility over the remaining term of the original lease. In the fourth quarter of 2018, the Company recorded a restructuring accrual of $0.1 million for future its rental payment obligation associated with vacated office space at its Fremont, California facility.

In 2017, the Company recorded a credit resulting from actual expenditures being less than originally accrued associated with the worldwide restructuring plan implemented in the first quarter of 2016.

Restructuring and severance activities during the years ended December 31, 2018 and December 31, 2017 were as follows (in thousands):

	Year Ended December 31,
	2018			2017
Balance at beginning of period	$	—		$	237
Restructuring expense incurred for the period		747			(49	)
Payments during the period		(618	)		(188	)
Balance at end of period	$	129		$	—