Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Cash flows from operating activities
Net income (loss)	$ (31,562)	$ 483,819
Gain from discontinued operations	16,330	547,994
Loss from continuing operations	(47,892)	(64,175)
Adjustments to reconcile net (loss) income to net cash used in operating activities
Non-cash interest expense	121	3,352
Loss on extinguishment of debt		25,011
Benefit from intraperiod tax allocation	(4,798)	(32,372)
Depreciation and amortization expense	3,211	2,813
Non-cash activity related to discontinued operations	(532)	10,241
Gain on deconsolidation of Silver Creek Pharmaceuticals, Inc.		(10,848)
Loss (gain) on sale of property and equipment	184	(439)
Premiums paid on marketable securities	(2)
Amortization and accretion on marketable securities	(398)
Stock-based compensation expense	2,326	11,110
Loss on equity method investment	1,658
Changes in operating assets and liabilities:
Prepaid expenses and other assets	(314)	(6,120)
Income taxes payable	361	1,844
Accounts payable, accrued expenses and other	1,083	(3,140)
Deferred rent	(1,704)	(334)
Net cash used in continuing operations for operating activities	(46,696)	(63,057)
Net cash used in discontinuing operations for operating activities		(37,964)
Net cash used in operating activities	(46,696)	(101,021)
Cash flows from investing activities
Purchase of property and equipment	(118)	(729)
Proceeds on sale of property and equipment		1,094
Proceeds from sale of business	23,000	575,000
Proceeds from maturities and sales of marketable securities	42,200
Purchases of marketable securities	(76,857)
Net cash (used in) provided by investing activities	(11,775)	571,363
Cash flows from financing activities
Payment of debt extinguishment costs		(20,124)
Proceeds from issuance of notes payable, net of issuance costs	14,632
Proceeds from exercise of options to purchase common stock		6,517
Repayment of debt		(175,000)
Payment of dividend		(140,000)
Net cash provided by (used in) financing activities	14,632	(324,613)
Net (decrease) increase in cash, cash equivalents and restricted cash	(43,839)	145,729
Cash, cash equivalents and restricted cash, beginning of period	94,217	22,300
Cash, cash equivalents and restricted cash, end of period	50,378	168,029
Non-cash investing and financing activities
Purchases of property and equipment in accounts payable, accrued expenses and other		159
Receivables related to property and equipment sale in other current assets		145
Supplemental disclosure of cash flows
Cash paid for income taxes		6,122
Cash paid for interest	$ 235	30,250
Silver Creek Pharmaceuticals Inc [Member]
Adjustments to reconcile net (loss) income to net cash used in operating activities
Gain on deconsolidation of Silver Creek Pharmaceuticals, Inc.		(10,848)
Cash flows from investing activities
Deconsolidation of Silver Creek Pharmaceuticals, Inc.		(4,002)
Cash flows from financing activities
Proceeds from issuance of Series C preferred stock by Silver Creek Pharmaceuticals, Inc., net of issuance costs		$ 3,994