Revenue Recognition - Allowance for Doubtful Accounts (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jan. 01, 2020	Dec. 31, 2019
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	$ 23,777	$ 16,604
Credit losses	4,393	18,862
Deductions	(10,546)	(10,053)
Foreign currency translation	(1,211)	173
Balance at end of period	16,413	$ 25,586
Accumulated earnings (losses)	$ 558,034			$ 632,809
Accounting Standards Update 2016-13
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Other current assets and other non-current assets			$ 13,400
Accumulated earnings (losses)			$ 2,900