Condensed Consolidated Statement of Shareholders' Equity - 3 months ended Mar. 31, 2018 - USD ($) $ in Thousands	Total	Common Stock	Retained Earnings	Other Comprehensive Loss
BALANCES AT Dec. 31, 2017 (in Shares) at Dec. 31, 2017	125,090,522	125,091,000
BALANCES AT Dec. 31, 2017 at Dec. 31, 2017	$ 831,245	$ 550,472	$ 294,741	$ (13,968)
Increase (Decrease) in Stockholders' Equity
Consolidated net (loss) income	$ (28,747)		(28,747)
Exercise of stock options (in Shares)	22,000	22,000
Exercise of stock options	$ 546	$ 546
Compensation and share issuances related to restricted stock awards	2,349	2,349
Stock-based compensation expense - stock options	3,159	$ 3,159
Foreign currency translation loss	(848)			(848)
Unrealized holding loss on available-for-sale securities	(1)			(1)
Akorn AG pension liability adjustment	4			4
Employee stock purchase plan		146,000
Employee stock purchase plan (in Shares)	$ 2,809	$ 2,809
BALANCES AT March 31, 2018 (in Shares) at Mar. 31, 2018	125,258,615	125,259,000
BALANCES AT March 31, 2018 at Mar. 31, 2018	$ 810,516	$ 559,335	$ 265,994	$ (14,813)