Revenue Recognition - Product Revenue Allowance and Accrual Activity (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Sep. 30, 2018	Jun. 30, 2018
Contractual Adjustments
Balance at Beginning of Period	$ 71,255	$ 62,164
Provisions related to current period sales	93,824	199,716
Adjustments related to prior period sales	(614)	(2,034)
Payments/returns relating to current period sales	(102,627)	(132,618)
Payments/returns relating to prior period sales	(2,207)	(55,973)
Balance at End of Period	59,631	71,255
Governmental Rebates
Balance at Beginning of Period	73,354	50,598
Provisions related to current period sales	20,719	71,514
Adjustments related to prior period sales	2,710	4,837
Payments/returns relating to current period sales	(52,040)	(2,453)
Payments/returns relating to prior period sales	(7,002)	(51,142)
Balance at End of Period	37,741	73,354
Revenue, Allowance [Roll Forward]
Balance at Beginning of Period	144,609	112,762
Provisions related to current period sales	114,543	271,230
Adjustments related to prior period sales	2,096	2,803
Payments/returns relating to current period sales	(154,667)	(135,071)
Payments/returns relating to prior period sales	(9,209)	(107,115)
Balance at End of Period	$ 97,372	$ 144,609