CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOW - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash Flows From Operating Activities:
Net Loss	$ (118,132)	$ (34,261)
Adjustments to Reconcile Net Loss to Net Cash Used in Operating Activities:
Depreciation and Amortization	1,028	1,366
Amortization of Intangible Assets	224	224
Amortization and Premium of Marketable Securities, Net	(155)	(23)
Loss on Sale or Disposal of Assets	10
Goodwill Impairment	90,976
Intangible Asset Impairment	18,677
(Gain)/Loss on Fair Value Remeasurement of Contingent Consideration	(13,600)	3,400
Non-Cash Income Tax Benefit	(765)
Stock-Based Compensation Expense	2,488	3,539
Changes in Operating Assets and Liabilities:
Accounts and Other Receivables	(1,635)	400
Prepaid and Other Current Assets	(144)	(989)
Other Assets		199
Accounts Payable and Accrued Expenses	(5,919)	(8,315)
Other Liabilities	(1,075)	(802)
Net Cash Used in Operating Activities	(28,022)	(35,262)
Cash Flows From Investing Activities:
Sales and Maturities of Marketable Securities	46,871	73,736
Purchases of Marketable Securities	(31,117)	(50,961)
Acquisition of Property and Equipment	(259)	(374)
Net Cash Provided by Investing Activities	15,495	22,401
Cash Flows From Financing Activities:
Net Proceeds from Stock Issuances	11,689	12,821
Proceeds from Issuance of Stock from Employee Benefit Plans	374	76
Net Cash Provided by Financing Activities	12,063	12,897
Net (Decrease) Increase in Cash and Cash Equivalents	(464)	36
Cash and Cash Equivalents at Beginning of Period	40,288	42,461
Cash and Cash Equivalents at End of Period	39,824	42,497
Non-cash Investing Activities
Accrued construction in progress	212	370
Non-cash Supplemental Disclosure
Shares issued to former Kolltan executive for settlement of severance	$ 38	$ 209