Revenues - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Oct. 01, 2017	Sep. 30, 2018	Oct. 01, 2017	Jan. 01, 2018	Dec. 31, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Increase (decrease) in retained earnings	$ 889,189,000		$ 889,189,000			$ 833,610,000
Decrease in revenues	(655,774,000)	$ (621,745,000)	(1,929,978,000)	$ (1,783,759,000)
Accrued rebates	30,100,000		30,100,000
Accrued returns	9,300,000		9,300,000
Estimated price adjustments, accounts receivable			29,000,000
Contract with customer, deferred revenues	90,800,000		90,800,000		$ 104,400,000
Contract with customer, deferred revenues, current	78,500,000		78,500,000
Contract with customer, deferred revenues, noncurrent	12,300,000		12,300,000
Contract with customer, revenue recognized	50,800,000		149,400,000
Deferred sales commission	2,300,000		2,300,000
Sales commissions	5,900,000		18,400,000
Accounting Standards Update 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Increase (decrease) in retained earnings					$ 2,600,000
Decrease in revenues	$ 0		$ 0