SCHEDULE II. VALUATION AND QUALIFYING ACCOUNTS (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Decrease in valuation allowance		$ (7,900)
Change in Estimate of Interest Deductions
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Decrease in valuation allowance			$ (5,400)
Allowance for Doubtful Accounts
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	$ 13,512	4,586	4,470
Charged to Cost and Expenses	1,960	7,507	380
Due to Currency Translation Adjustments	(81)	370	(149)
Other	(7,890)	1,049	(115)
Balance at End of Period	7,501	13,512	4,586
Deferred Tax Assets - Valuation Allowance
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	127,074	137,450	172,846
Charged to Cost and Expenses	10,133	(7,395)	(20,104)
Due to Currency Translation Adjustments	3,331	448	(8,612)
Other	77	(3,429)	(6,680)
Balance at End of Period	140,615	127,074	137,450
Valuation Allowance, Tax Credit Carryforward
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Decrease in valuation allowance	(15,500)
Valuation Allowance, Deferred Tax Asset, liquidation and Merger of Entities [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Decrease in valuation allowance		(5,600)
Capital Loss Carryforward
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Decrease in valuation allowance			$ (1,100)
Pension Adjustments
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Decrease in valuation allowance	(13,000)	(900)
Valuation Allowance, Deferred Tax Asset, Tax Credit [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Decrease in valuation allowance		$ (800)
Tax Rate Change
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Decrease in valuation allowance	$ (3,700)