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

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, which was announced in March 2019.

A reconciliation of the beginning and ending restructuring liability, which is included in accrued wages and benefits in the Condensed Consolidated Balance Sheets as of June 30, 2020 and December 31, 2019, is as follows:

	Three Months Ended			Six Months Ended
(In thousands)	June 30, 2020			June 30, 2020
Balance at beginning of period	$	133		$	1,568
Plus: Amounts charged to cost and expense		1,192			1,745
Less: Amounts paid		(967	)		(2,955	)
Balance as of June 30, 2020	$	358		$	358

(In thousands)	December 31, 2019
Balance as of December 31, 2018	$	185
Plus: Amounts charged to cost and expense		6,014
Less: Amounts paid		(4,631	)
Balance as of December 31, 2019	$	1,568

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

	Three Months Ended				Six Months Ended
	June 30,				June 30,
(In thousands)	2020		2019		2020		2019
Selling, general and administrative expenses	$	489	$	703	$	572	$	1,547
Research and development expenses		681		647		1,117		1,231
Cost of sales		22		50		56		685
Total restructuring expenses	$	1,192	$	1,400	$	1,745	$	3,463

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

	Three Months Ended				Six Months Ended
	June 30,				June 30,
(In thousands)	2020		2019		2020		2019
Domestic	$	1,192	$	541	$	1,743	$	825
International		—		859		2		2,638
Total restructuring expenses	$	1,192	$	1,400	$	1,745	$	3,463