Employee benefit plans (Tables)

12 Months Ended

Dec. 31, 2023

Defined Benefit Plan Disclosure [Line Items]

Schedule of Net Periodic Defined Benefit Cost (Income)

	Years ended December 31,
	2021		2022		2023
	(In thousands)
Net periodic pension cost:
Interest cost	$	947	$	1,138	$	1,619
Expected return on plan assets		(1,603)		(1,552)		(1,452)
Plan settlement		—		104		4,911
Recognized actuarial losses		1,562		1,664		1,391
Total	$	906	$	1,354	$	6,469

Defined Benefit Pension Plans

Defined Benefit Plan Disclosure [Line Items]

Expected Benefit Payments

Years ending December 31,	Amount
	(In thousands)
2024	$	3,012
2025		2,923
2026		2,849
2027		2,766
2028		2,668
Next 5 years		11,725

Funded Status of Defined Benefit Plans

	December 31,
	2022		2023
	(In thousands)
Change in projected benefit obligations (PBO):
Benefit obligations at beginning of the year	$	50,367	$	36,090
Interest cost		1,138		1,619
Plan settlement		(188)		(5,537)
Actuarial (gains) losses		(10,777)		265
Change in currency exchange rates		(965)		116
Benefits paid		(3,485)		(3,115)
Benefit obligations at end of the year		36,090		29,438
Change in plan assets:
Fair value of plan assets at beginning of the year		47,940		34,126
Actual return on plan assets		(10,263)		2,009
Employer contributions		1,228		196
Plan settlement		(188)		(5,537)
Change in currency exchange rates		(1,106)		131
Benefits paid		(3,485)		(3,115)
Fair value of plan assets at end of year		34,126		27,810
Funded status	$	(1,964)	$	(1,628)
Amounts recognized in the balance sheet:
Noncurrent pension asset	$	1,105	$	—
Accrued pension costs:
Current		(57)		(57)
Noncurrent		(3,012)		(1,571)
Total		(1,964)		(1,628)
Accumulated other comprehensive loss - actuarial losses, net		27,530		21,802
Total	$	25,566	$	20,174
Accumulated benefit obligations (ABO)	$	36,090	$	29,438

Changes in Other Comprehensive Income (Loss)

	Years ended December 31,
	2021		2022		2023
	(In thousands)
Changes in plan assets and benefit obligations recognized in   other comprehensive income:
Net actuarial gain (loss) arising during the year	$	1,618	$	(1,034)	$	(574)
Plan settlement		—		104		4,911
Amortization of unrecognized net actuarial gain (loss)		(1,562)		1,664		1,391
Total	$	56	$	734	$	5,728

Information Concerning Defined Benefit Pension Plans (Including Certain Plans for Which ABO Exceeds Fair Value of Plan Assets)

	December 31,
	2022		2023
	(In thousands)
PBO at end of the year:
U.S. plan	$	30,254	$	29,438
U.K. plan		5,836		—
Total	$	36,090	$	29,438
Fair value of plan assets at end of the year:
U.S. plan	$	27,185	$	27,810
U.K. plan		6,941		—
Total	$	34,126	$	27,810
Plans for which the ABO exceeds plan assets (only our U.S. plan):
PBO	$	30,254	$	29,438
ABO		30,254		29,438
Fair value of plan assets		27,185		27,810

Summary of Assumptions Used to Determine Net Benefit Obligation

	Years ended December 31,
Rate	2021		2022		2023
Discount rate	2.1	%	2.3	%	5.1	%
Long-term rate of return on plan assets	3.3	%	3.3	%	4.9	%

Schedule of composition of our pension plan assets by fair value level

	Fair Value Measurements
			Quoted prices		Significant other		Significant
			in active		observable		unobservable		Assets measured
	Total		markets (Level 1)		inputs (Level 2)		inputs (Level 3)		at NAV
	(In thousands)
December 31, 2022:
U.S.:
Equities	$	8,591	$	694	$	—	$	—	$	7,897
Fixed income		15,954		149		—		—		15,805
Cash and other		2,640		1,903		—		44		693
U.K. - Other		6,941		1,104		—		5,837		—
Total	$	34,126	$	3,850	$	—	$	5,881	$	24,395

As noted above, in March 2021 we purchased a bulk annuity for our U.K. pension plan and such annuity is considered a Level 3 asset included with “U.K. – Other” in the table above.

	Fair Value Measurements
			Quoted prices		Significant other		Significant
			in active		observable		unobservable		Assets measured
	Total		markets (Level 1)		inputs (Level 2)		inputs (Level 3)		at NAV
	(In thousands)
December 31, 2023:
U.S.:
Equities	$	7,786	$	—	$	—	$	—	$	7,786
Fixed income		18,733		—		—		—		18,733
Cash and other		1,291		489		—		41		761
Total	$	27,810	$	489	$	—	$	41	$	27,280