Schedule II - Valuation and Qualifying Accounts and Reserves (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Allowance for Doubtful Accounts [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Valuation Allowances and Reserves, Balance	$ 57,207	$ 57,609	$ 45,608	$ 24,583
Valuation Allowances and Reserves, Additions for Charges to Cost and Expense	13,970	15,387	13,280
Valuation Allowances and Reserves, Deductions	(15,945)	(13,012)	(21,829)
Valuation Allowances and Reserves, Reserves of Businesses Acquired	$ 1,573	9,626	29,574
Allowance For Estimated Returns, Discounts, And Allowances [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Valuation Allowances and Reserves, Balance		42,325	38,345	$ 32,774
Valuation Allowances and Reserves, Additions for Charges to Cost and Expense		1,885,517	1,670,911
Valuation Allowances and Reserves, Deductions		(1,884,250)	(1,673,040)
Valuation Allowances and Reserves, Reserves of Businesses Acquired		$ 2,713	$ 7,700