In November 2017, the Company implemented a restructuring plan (“November 2017 Plan”) to reduce its sales and marketing headcount and centralize its sales function in its San Mateo, CA headquarters. The total restructuring costs associated with the November 2017 Plan was $5.1 million and was primarily lease termination costs and employee severance, of which $0.1 million was reversed during the three months ended March 31, 2019, $3.5 million was recognized during the year ended December 31, 2018 and $1.7 million was recognized during the year ended December 31, 2017. The restructuring costs incurred during the year ended December 31, 2018 were primarily due to the changes in estimated contract termination costs resulting from lower estimated sublease cash payments, and related leasehold impairment costs as the Company estimated that the leasehold improvements at the vacated facility would not be recoverable from the estimated sublease cash flows. The restructuring costs incurred during the three months ended March 31, 2019 were primarily due to the changes in estimated contract termination costs.

The November 2017 Plan was subject to applicable laws and consultation processes, as a part of the Company’s strategic plan to focus on its core product and improve efficiencies. In connection with these actions, the Company incurred the following pre-tax costs:

	Three Months Ended March 31,
(in thousands)	2019			2018
Employee severance	$	—		$	5
Contract termination and other costs		(66	)		—
Total restructuring costs	$	(66	)	$	5

As of December 31, 2018, $0.6 million and $0.3 million were recorded in accrued expenses and other current liabilities and other non-current liabilities, respectively. Upon adoption of ASC 842 on January 1, 2019, amounts previously accrued in restructuring for operating leases were derecognized as they are included in ROU assets in the condensed consolidated balance sheets (see Note 8 for additional information). As of March 31, 2019, the remaining amount of accrued restructuring for contract termination costs was nominal.