CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Cash flows from operating activities:
Net income (loss)	$ 13,796	$ (31,544)	$ 43,664	$ (65,437)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation			91,519	98,284
Amortization			5,989	10,003
Change in fair value to the unit adjustment liability and loss on dilution and sale of equity method investment	0	44,788	0	58,494
Deferred income tax expense (benefit)			2,018	(2,015)
Equity income of unconsolidated entities, net	0	(3,205)	0	(5,686)
Dividends from unconsolidated entities			93	16
Contract estimated forward loss provision for Harsco Rail Segment		40,050	0	40,050	$ 45,100
Other, net			2,567	1,911
Changes in assets and liabilities:
Accounts receivable			(26,633)	4,055
Inventories			(30,112)	(24,295)
Accounts payable			9,045	(10,740)
Accrued interest payable			287	6,245
Accrued compensation			979	4,481
Advances on contracts and other customer advances			(6,534)	15,352
Retirement plan liabilities, net			(17,890)	(17,151)
Other assets and liabilities			7,913	(8,721)
Net cash provided by operating activities			82,905	104,846
Cash flows from investing activities:
Purchases of property, plant and equipment			(64,131)	(49,946)
Proceeds from sales of assets			10,746	7,178
Purchases of businesses, net of cash acquired			0	(26)
Proceeds from sale of equity investment			0	165,640
Other investing activities, net			4,450	7,058
Net cash provided (used) by investing activities			(48,935)	129,904
Cash flows from financing activities:
Short-term borrowings, net			1,915	(1,527)
Current maturities and long-term debt:
Additions			26,000	50,835
Reductions			(65,245)	(275,768)
Cash dividends paid on common stock			0	(4,105)
Dividends paid to noncontrolling interests			(1,783)	(1,702)
Purchase of noncontrolling interests			(3,412)	(4,731)
Stock-based compensation - Employee taxes paid			(1,607)	(91)
Proceeds from cross-currency interest rate swap termination			0	16,625
Deferred pension underfunding payment to unconsolidated affiliate			0	(20,640)
Deferred financing costs			(42)	(946)
Other financing activities, net			(370)	0
Net cash used by financing activities			(44,544)	(242,050)
Effect of exchange rate changes on cash and cash equivalents, including restricted cash			4,058	7,455
Net increase (decrease) in cash and cash equivalents, including restricted cash			(6,516)	155
Cash and cash equivalents, including restricted cash, at beginning of period			71,879	79,756	79,756
Cash and cash equivalents, including restricted cash, at end of period	$ 65,363	$ 79,911	$ 65,363	$ 79,911	$ 71,879