Employee Benefit Plans (Details 3) - Pension Plan $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($) market shares	Dec. 31, 2021 USD ($) shares	Dec. 31, 2020 USD ($)
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Expected long-term rates of return on plan assets for next year (as a percent)		5.50%
Expected long-term rates of return on plan assets		4.70%	5.10%	5.60%
U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation		$ 209,200	$ 277,000
Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Abstract]
Projected benefit obligation		209,200	277,000
Accumulated benefit obligation		209,200	277,000
Fair value of plan assets		$ 177,000	$ 232,900
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Number of capital market results simulated in the model for expected return on plan assets | market		1,000
Period for which results of capital markets are simulated		20 years
Expected long-term rates of return on plan assets for next year (as a percent)		7.00%
Expected long-term rates of return on plan assets		6.30%	6.80%	7.00%
Number of shares of Company's common stock included in plan assets | shares		310,000	310,000
Fair values of plan assets		$ 177,044	$ 232,947	$ 226,125
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	$ 177,044	232,947	226,125
Employer contributions		1,706	4,219
Fair value of plan assets at end of year		$ 177,044	$ 232,947	$ 226,125
U.S. Plans | Forecast
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Expected long-term rates of return on plan assets	7.00%
U.S. Plans | Domestic equity securities
Defined Benefit Plan, Information about Plan Assets [Abstract]
Percentage of Plan Assets at December 31		21.00%	22.80%
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		$ 1,951	$ 5,180
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	$ 1,951	5,180
Fair value of plan assets at end of year		$ 1,951	5,180
U.S. Plans | Domestic equity securities | Minimum
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Target Long-Term Allocation (less than 5% for Cash and cash equivalents)		18.00%
U.S. Plans | Domestic equity securities | Maximum
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Target Long-Term Allocation (less than 5% for Cash and cash equivalents)		28.00%
U.S. Plans | Domestic mutual funds—equities
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		$ 35,177	48,411
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	35,177	48,411
Fair value of plan assets at end of year		$ 35,177	$ 48,411
U.S. Plans | International equity securities
Defined Benefit Plan, Information about Plan Assets [Abstract]
Percentage of Plan Assets at December 31		22.20%	22.50%
U.S. Plans | International equity securities | Minimum
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Target Long-Term Allocation (less than 5% for Cash and cash equivalents)		17.00%
U.S. Plans | International equity securities | Maximum
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Target Long-Term Allocation (less than 5% for Cash and cash equivalents)		27.00%
U.S. Plans | International equities—mutual funds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		$ 39,287	$ 50,783
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	39,287	50,783
Fair value of plan assets at end of year		$ 39,287	$ 50,783
U.S. Plans | Harsco common stock
Defined Benefit Plan, Information about Plan Assets [Abstract]
Percentage of Plan Assets at December 31		1.10%	2.20%
U.S. Plans | Fixed income securities
Defined Benefit Plan, Information about Plan Assets [Abstract]
Percentage of Plan Assets at December 31		44.60%	45.90%
U.S. Plans | Fixed income securities | Minimum
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Target Long-Term Allocation (less than 5% for Cash and cash equivalents)		41.00%
U.S. Plans | Fixed income securities | Maximum
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Target Long-Term Allocation (less than 5% for Cash and cash equivalents)		51.00%
U.S. Plans | Mutual funds - bonds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		$ 78,943	$ 105,114
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	78,943	105,114
Fair value of plan assets at end of year		$ 78,943	$ 105,114
U.S. Plans | Other
Defined Benefit Plan, Information about Plan Assets [Abstract]
Percentage of Plan Assets at December 31		11.20%	8.80%
U.S. Plans | Other | Minimum
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Target Long-Term Allocation (less than 5% for Cash and cash equivalents)		4.00%
U.S. Plans | Other | Maximum
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Target Long-Term Allocation (less than 5% for Cash and cash equivalents)		14.00%
U.S. Plans | Other mutual funds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		$ 6,699	$ 9,371
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	6,699	9,371
Fair value of plan assets at end of year		$ 6,699	$ 9,371
U.S. Plans | Cash and cash equivalents
Defined Benefit Plan, Information about Plan Assets [Abstract]
Percentage of Plan Assets at December 31		1.00%	0.00%
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		$ 1,780	$ 1,624
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	1,780	1,624
Fair value of plan assets at end of year		$ 1,780	1,624
U.S. Plans | Cash and cash equivalents | Maximum
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Target Long-Term Allocation (less than 5% for Cash and cash equivalents)		5.00%
U.S. Plans | Partnership [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		$ 13,207	12,464
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	13,207	12,464
Fair value of plan assets at end of year		13,207	12,464
U.S. Plans | Defined Benefit Plan, Equity Securities, Common Stock, Employer, Related Party [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Value of shares of Company's common stock included in plan assets		2,000	5,200
U.S. Plans | Level 1
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		163,837	220,483
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	163,837	220,483
Fair value of plan assets at end of year		163,837	220,483
U.S. Plans | Level 1 | Domestic equity securities
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		1,951	5,180
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	1,951	5,180
Fair value of plan assets at end of year		1,951	5,180
U.S. Plans | Level 1 | Domestic mutual funds—equities
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		35,177	48,411
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	35,177	48,411
Fair value of plan assets at end of year		35,177	48,411
U.S. Plans | Level 1 | International equities—mutual funds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		39,287	50,783
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	39,287	50,783
Fair value of plan assets at end of year		39,287	50,783
U.S. Plans | Level 1 | Mutual funds - bonds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		78,943	105,114
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	78,943	105,114
Fair value of plan assets at end of year		78,943	105,114
U.S. Plans | Level 1 | Other mutual funds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		6,699	9,371
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	6,699	9,371
Fair value of plan assets at end of year		6,699	9,371
U.S. Plans | Level 1 | Cash and cash equivalents
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		1,780	1,624
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	1,780	1,624
Fair value of plan assets at end of year		1,780	1,624
U.S. Plans | Level 1 | Partnership [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0	0
Fair value of plan assets at end of year		0	0
U.S. Plans | Fair Value Measured at Net Asset Value Per Share [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		13,207	12,464
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	13,207	12,464
Fair value of plan assets at end of year		13,207	12,464
U.S. Plans | Fair Value Measured at Net Asset Value Per Share [Member] | Domestic equity securities
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0	0
Fair value of plan assets at end of year		0	0
U.S. Plans | Fair Value Measured at Net Asset Value Per Share [Member] | Domestic mutual funds—equities
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0	0
Fair value of plan assets at end of year		0	0
U.S. Plans | Fair Value Measured at Net Asset Value Per Share [Member] | International equities—mutual funds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0	0
Fair value of plan assets at end of year		0	0
U.S. Plans | Fair Value Measured at Net Asset Value Per Share [Member] | Mutual funds - bonds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0	0
Fair value of plan assets at end of year		0	0
U.S. Plans | Fair Value Measured at Net Asset Value Per Share [Member] | Other mutual funds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0	0
Fair value of plan assets at end of year		0	0
U.S. Plans | Fair Value Measured at Net Asset Value Per Share [Member] | Cash and cash equivalents
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0	0
Fair value of plan assets at end of year		0	0
U.S. Plans | Fair Value Measured at Net Asset Value Per Share [Member] | Partnership [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		13,207	12,464
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	13,207	12,464
Fair value of plan assets at end of year		13,207	12,464
International Plans
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation		593,400	1,016,100
Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Abstract]
Projected benefit obligation		25,300	988,600
Accumulated benefit obligation		22,600	984,700
Fair value of plan assets		$ 9,400	$ 939,300
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Expected long-term rates of return on plan assets for next year (as a percent)		5.10%
Expected long-term rates of return on plan assets		4.40%	4.70%	5.20%
Fair values of plan assets		$ 607,234	$ 973,252	$ 957,177
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	607,234	973,252	957,177
Employer contributions		22,614	25,077
Fair value of plan assets at end of year		$ 607,234	$ 973,252	$ 957,177
International Plans | Equity Securities [Member]
Defined Benefit Plan, Information about Plan Assets [Abstract]
Percentage of Plan Assets at December 31		24.80%	27.90%
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Target Long-Term Allocation (less than 5% for Cash and cash equivalents)		26.50%
International Plans | Mutual funds - equities
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		$ 150,813	$ 271,811
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	150,813	271,811
Fair value of plan assets at end of year		$ 150,813	$ 271,811
International Plans | Fixed income securities
Defined Benefit Plan, Information about Plan Assets [Abstract]
Percentage of Plan Assets at December 31		65.50%	63.60%
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Target Long-Term Allocation (less than 5% for Cash and cash equivalents)		65.50%
International Plans | Mutual funds - bonds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		$ 392,960	$ 613,243
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	392,960	613,243
Fair value of plan assets at end of year		392,960	613,243
International Plans | Insurance contracts
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		4,636	5,684
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	4,636	5,684
Fair value of plan assets at end of year		$ 4,636	$ 5,684
International Plans | Other
Defined Benefit Plan, Information about Plan Assets [Abstract]
Percentage of Plan Assets at December 31		8.20%	7.80%
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Target Long-Term Allocation (less than 5% for Cash and cash equivalents)		8.00%
International Plans | Other mutual funds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		$ 49,805	$ 75,651
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	49,805	75,651
Fair value of plan assets at end of year		$ 49,805	$ 75,651
International Plans | Cash and cash equivalents
Defined Benefit Plan, Information about Plan Assets [Abstract]
Percentage of Plan Assets at December 31		1.50%	0.70%
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Target Long-Term Allocation (less than 5% for Cash and cash equivalents)		0.00%
Fair values of plan assets		$ 9,020	$ 6,863
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	9,020	6,863
Fair value of plan assets at end of year		9,020	6,863
International Plans | Level 1
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		9,020	6,863
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	9,020	6,863
Fair value of plan assets at end of year		9,020	6,863
International Plans | Level 1 | Mutual funds - equities
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0	0
Fair value of plan assets at end of year		0	0
International Plans | Level 1 | Mutual funds - bonds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0	0
Fair value of plan assets at end of year		0	0
International Plans | Level 1 | Insurance contracts
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0	0
Fair value of plan assets at end of year		0	0
International Plans | Level 1 | Other mutual funds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0	0
Fair value of plan assets at end of year		0	0
International Plans | Level 1 | Cash and cash equivalents
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		9,020	6,863
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	9,020	6,863
Fair value of plan assets at end of year		9,020	6,863
International Plans | Level 2
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		598,214	966,389
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	598,214	966,389
Fair value of plan assets at end of year		598,214	966,389
International Plans | Level 2 | Mutual funds - equities
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		150,813	271,811
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	150,813	271,811
Fair value of plan assets at end of year		150,813	271,811
International Plans | Level 2 | Mutual funds - bonds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		392,960	613,243
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	392,960	613,243
Fair value of plan assets at end of year		392,960	613,243
International Plans | Level 2 | Insurance contracts
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		4,636	5,684
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	4,636	5,684
Fair value of plan assets at end of year		4,636	5,684
International Plans | Level 2 | Other mutual funds
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		49,805	75,651
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	49,805	75,651
Fair value of plan assets at end of year		49,805	75,651
International Plans | Level 2 | Cash and cash equivalents
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Fair values of plan assets		0	0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	$ 0	0
Fair value of plan assets at end of year		$ 0	$ 0
International, Other Than United Kingdom [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Pension plan assets as a percentage of international plan assets		6.00%
United Kingdom
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Expected long-term rates of return on plan assets for next year (as a percent)		5.00%	4.30%
Pension plan assets as a percentage of international plan assets		94.00%