During the second half of 2019, the Company initiated a restructuring plan to realign its expense structure with the reduction in revenue experienced in recent years and overall Company objectives. As part of this restructuring plan, the Company announced plans to reduce its overall operating expenses, both in the U.S. and internationally. Management continued to assess the efficiency of operations during 2020 and 2021 and, in turn, consolidated locations and personnel, among other things, where possible.

In February 2019, the Company announced the restructuring of a certain portion of its workforce predominantly in Germany, which included the closure of the Company’s office location in Munich, Germany accompanied by relocation or severance benefits for the affected employees. Voluntary early retirement was offered to certain other employees and was announced in March 2019 and again in August 2020.

The cumulative amount of restructuring expenses incurred as of March 31, 2021 for the restructuring plans was $12.5 million.

A reconciliation of the beginning and ending restructuring liability, which is included in accrued wages and benefits in the Consolidated Balance Sheets is as follows:

(In thousands)	As of March 31, 2021
Balance as of December 31, 2020	$	4,186
Plus: Amounts charged to cost and expense		301
Less: Amounts paid		(2,410	)
Balance as of March 31, 2021	$	2,077

Restructuring expenses included in the Condensed Consolidated Statements of Income (Loss) were as follows:

	Three Months Ended
	March 31,
(In thousands)	2021		2020
Cost of revenue		15		34
Selling, general and administrative expenses	$	142	$	83
Research and development expenses		144		436
Total restructuring expenses	$	301	$	553

The following table represents the components of restructuring expense by geographic area were as follows:

	Three Months Ended
	March 31,
(In thousands)	2021		2020
Domestic	$	209	$	551
International		92		2
Total restructuring expenses	$	301	$	553