Revenue Recognition - Product Revenue Allowance and Accrual Activity (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Contractual Adjustments
Balance at Beginning of Period	$ 62,164	$ 47,600	$ 30,177
Provisions related to current period sales	389,861	314,537	224,894
Adjustments related to prior period sales	(2,330)	(3,949)	(2,348)
Payments/returns relating to current period sales	(333,694)	(253,545)	(181,150)
Payments/returns relating to prior period sales	(58,802)	(42,479)	(23,973)
Balance at End of Period	57,199	62,164	47,600
Governmental Rebates
Balance at Beginning of Period	50,598	51,399	25,767
Provisions related to current period sales	105,034	112,167	93,035
Adjustments related to prior period sales	7,903	1,661	(6,052)
Payments/returns relating to current period sales	(75,920)	(61,569)	(41,636)
Payments/returns relating to prior period sales	(58,501)	(53,060)	(19,715)
Balance at End of Period	29,114	50,598	51,399
Revenue, Allowance [Roll Forward]
Balance at Beginning of Period	112,762	98,999	55,944
Provisions related to current period sales	494,895	426,704	317,929
Adjustments related to prior period sales	5,573	(2,288)	(8,400)
Payments/returns relating to current period sales	(409,614)	(315,114)	(222,786)
Payments/returns relating to prior period sales	(117,303)	(95,539)	(43,688)
Balance at End of Period	$ 86,313	$ 112,762	$ 98,999