Retirement Plans (Tables)

3 Months Ended

Mar. 29, 2020

Defined Benefit Pension Plans

Net Periodic Pension and Postretirement Benefit Costs

For the three months ended March 29, 2020 and March 31, 2019, Teradyne’s net periodic pension cost was comprised of the following:

	For the Three Months Ended
	March 29, 2020						March 31, 2019
	United States			Foreign			United States			Foreign
	(in thousands)
Service cost	$	433		$	201		$	405		$	188
Interest cost		1,522			115			1,795			173
Expected return on plan assets		(1,233	)		(15	)		(1,511	)		(7	)
Total net periodic pension cost	$	722		$	301		$	689		$	354

Postretirement Benefit Plans

Net Periodic Pension and Postretirement Benefit Costs

For the three months ended March 29, 2020 and March 31, 2019, Teradyne’s net periodic postretirement benefit cost was comprised of the following:

	For the Three Months Ended
	March 29,			March 31,
	2020			2019
	(in thousands)
Service cost	$	11		$	9
Interest cost		62			85
Amortization of prior service credit		(2	)		(48	)
Total net periodic postretirement benefit cost	$	71		$	46