SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Allowance for doubtful accounts
Changes in valuation and qualifying accounts
Balance at Beginning of Period		$ 12,827	$ 15,943	$ 7,768
Additions: Charged to Costs and Expenses		1,227	1,743	1,172
Additions: Charged to Other Accounts	[1]	3,792	(1,037)	9,501
Deductions	[2]	1,844	3,822	2,498
Balance at End of Period		16,002	12,827	15,943
SEC Schedule, 12-09, Valuation Allowance, Deferred Tax Asset [Member]
Changes in valuation and qualifying accounts
Balance at Beginning of Period		69,400	68,694	47,849
Additions: Charged to Costs and Expenses		3,691	1,891	16,222
Additions: Charged to Other Accounts	[1]	(481)	2,437	4,854
Deductions	[2]	1,064	3,622	231
Balance at End of Period		$ 71,546	$ 69,400	$ 68,694

[1] Currency translation adjustment, additions from acquisitions and other adjustments.

[2] For the Allowance for doubtful accounts, deductions relate to uncollectible accounts written-off, net of recoveries. For the Deferred tax asset valuation allowance, deductions relate to the reversal of valuation allowances due to the realization of net operating loss carryforwards.