Valuation and Qualifying Accounts (Details) - SEC Schedule, 12-09, Allowance, Credit Loss [Member] - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Allowance for Doubtful Accounts, Balance at beginning of year		$ 75,588	$ 56,291	$ 52,256
Allowance for doubtful accounts, Charged to Income		26,220	34,936	12,887
SEC Schedule, 12-09, Valuation Allowances and Reserves, Additions, Charge to Other Account	[1]	(681)	(1,958)	2,831
Allowance for Doubtful Accounts, Write-down		34,392	13,681	11,683
Allowance for Doubtful Accounts, Balance at end of year		$ 66,735	$ 75,588	$ 56,291

[1] “Other” primarily includes the effect of fluctuations in foreign currencies and the allowance for doubtful accounts of the businesses acquired and disposed of by the company.