Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 114,322	$ 49,060
Investments in marketable securities	448,198	309,502
Accounts receivable	10,836	9,464
Inventories	8,070	4,623
Prepaid expenses and other current assets	10,607	19,316
Total current assets	592,033	391,965
Investments in marketable securities	42,673
Property and equipment, less accumulated depreciation of $13,461 and $12,515 at March 31, 2018 and December 31, 2017, respectively	8,910	9,062
In-process research & development	23,000	23,000
Goodwill	197,797	197,797
Other non-current assets	5,592	5,200
Total Assets	870,005	627,024
Current liabilities:
Accounts payable, accrued expenses, and other current liabilities	43,678	53,890
Deferred reimbursements	7,750	7,750
Derivative liability	80,577
Contingent consideration payable	8,700	8,400
Total current liabilities	140,705	70,040
Deferred reimbursements	14,156	14,156
Convertible notes	166,768	164,167
Contingent consideration payable	17,800	17,000
Deferred income taxes	6,465	6,465
Other non-current liability	2,494	2,346
Total liabilities	348,388	274,174
Commitments and contingencies
Stockholders' equity:
Common stock, $0.01 par value, 250,000,000 shares authorized 187,972,218 and 166,989,790 shares issued and outstanding at March 31, 2018 and December 31, 2017, respectively	1,929	1,721
Additional paid-in capital	1,621,479	1,400,758
Accumulated other comprehensive loss:
Foreign currency translation adjustment	(3,847)	(1,659)
Unrealized loss on available-for-sale securities	(877)	(436)
Warrants	16,076	16,076
Accumulated deficit	(1,113,143)	(1,063,610)
Total stockholders' equity	521,617	352,850
Total Liabilities and Stockholders' Equity	$ 870,005	$ 627,024

Sum of the carrying values as of the balance sheet date of obligations incurred through that date and due within one year (or the operating cycle, if longer), including liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received, taxes, interest, rent and utilities, accrued salaries and bonuses, payroll taxes and fringe benefits.

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Period Type:	instant

- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.