Accounts Payable, Accrued Expenses and Other Liabilities (Schedule of Accounts Payable and Accrued Liabilities) (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Accounts Payable, Accrued Expenses and Other Liabilities [Abstract]
Accounts payable	$ 14,977	$ 18,975
Accrued employee compensation	14,135	26,483
Accrued contracted services	76,592	74,486
Accrued rebates, discounts and other incentives	25,422	21,529
Operating lease liabilities	6,596	6,456
Other liabilities	6,796	6,039
Accounts payable, accrued expenses and other liabilities	$ 144,518	$ 153,968