Significant Accounting Policies - Accrued Expenses and Other Payables (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Mar. 31, 2019
Accounting Policies [Abstract]
Accrued compensation and benefits	$ 16,174	$ 19,312
Excise and other tax liabilities	12,737	10,481
Derivative liabilities	31,108	88,932
Accrued interest	39,865	24,882
Product exchange liabilities	7,486	5,945
Gavilon legal matter settlement (Note 9)	12,500	12,500
Contingent consideration liability (Note 4)	190,000
Other	26,256	29,679
Total	$ 336,126	$ 191,731

Business Combination, Fair Value of Consideration To Be Paid In Installments

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Represents the carrying value as of the balance sheet date of obligations incurred through that date and payable for product exchange liabilities.

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Amount of obligations incurred classified as other, payable within one year or the normal operating cycle, if longer.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Aggregate carrying amount of the estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs.

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