Income Taxes (Details 2) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Line Items]
Foreign earnings before tax	$ 20,468	$ 18,646	$ (8,813)
Contract estimated forward loss provision for Harsco Rail Segment	45,050	0	0
Restructuring & impairment charges with no tax benefit		24,300
Differences on international earnings and remittances	2,000	5,100
Foreign Income Tax Expense (Benefit), Continuing Operations	16,300	23,300
U.S. earnings before tax	(99,939)	16,169	22,951
Valuation allowance related to sale of Brand	16,100
Operating loss carryforwards	80,178	77,151
Capital loss carryforwards	18,163	2,102
Deferred Tax Assets, Valuation Allowance	146,097	110,680
Undistributed earnings indefinitely reinvested outside United States	528,000	547,000
Interest and penalties recognized	1,700		2,100
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	1,100	2,800	$ 2,800
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit	900
Pension adjustments
Income Tax Disclosure [Line Items]
Non-cash tax expense		16,100
Currency translation
Income Tax Disclosure [Line Items]
Non-cash tax expense		(11,500)
UK tax rate changes
Income Tax Disclosure [Line Items]
Non-cash tax expense		(6,300)
Infrastructure Transaction
Income Tax Disclosure [Line Items]
Non-cash tax expense		13,200
Capital loss on Equity Investment in Brand [Member]
Income Tax Disclosure [Line Items]
Valuation Allowances and Reserves, Balance	16,100
Forward loss Provisions in SBB contract [Member]
Income Tax Disclosure [Line Items]
Valuation Allowances and Reserves, Balance	13,500
Current Year Pension Adjustments recorded through Accumulated Other Comprehensive Income (Loss) [Member]
Income Tax Disclosure [Line Items]
Valuation Allowances and Reserves, Balance	19,200
Expiring between 2018 and 2021
Income Tax Disclosure [Line Items]
Capital loss carryforwards	18,200
International operations
Income Tax Disclosure [Line Items]
Operating loss carryforwards	68,600
Operating loss carryforwards not subject to expiration	56,700
Operating losses subject to expiration	11,900
Unrecognized Tax Benefits, Increase (Decrease) Resulting from Changes in Enacted Legislation		$ (7,800)
U.S. state
Income Tax Disclosure [Line Items]
Operating loss carryforwards	11,600
U.S. state | Expiring between 2017 and 2020
Income Tax Disclosure [Line Items]
Operating loss carryforwards	1,400
U.S. state | Expiring between 2021 and 2025
Income Tax Disclosure [Line Items]
Operating loss carryforwards	3,600
U.S. state | Expiring between 2026 and 2030
Income Tax Disclosure [Line Items]
Operating loss carryforwards	3,300
U.S. state | Expiring between 2031 and 2036
Income Tax Disclosure [Line Items]
Operating loss carryforwards	$ 3,300