Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Cash flows from operating activities
Net loss	$ (30,153)	$ (38,658)
Loss from discontinued operations	(947)	(943)
Loss from continuing operations	(29,206)	(37,715)
Adjustments to reconcile net loss to net cash used in operating activities
Non-cash interest expense	1,508	2,190
Depreciation and amortization expense	1,182	1,198
Stock-based compensation expense	796	2,510
Changes in operating assets and liabilities:
Accounts receivable	232	11
Accounts payable, accrued expenses and other	8,054	(2,231)
Other assets and liabilities, net	(690)	1,324
Net cash used by continuing operations for operating activities	(18,124)	(32,713)
Net cash provided by (used in) discontinuing operations for operating activities	7,968	(20,810)
Net cash used in operating activities	(10,156)	(53,523)
Cash flows from investing activities
Purchases of marketable securities		(84,262)
Purchases of property and equipment	(290)	(1,229)
Net cash used in investing activities	(290)	(85,491)
Cash flows from financing activities
Proceeds from exercise of options to purchase common stock	4,053	1,645
Proceeds from issuance of preferred stock by Silver Creek Pharmaceuticals, Inc.	2,024
Net cash provided by financing activities	6,077	1,645
Net decrease in cash and cash equivalents	(4,369)	(137,369)
Cash and cash equivalents, beginning of period	21,524	185,606
Cash and cash equivalents, end of period	17,155	48,237
Non-cash investing and financing activities
Purchases of property and equipment in accounts payable, accrued expenses and other	34	388
Receivables related to stock option exercises in prepaid expenses and other current assets	76	53
Supplemental disclosure of cash flows
Cash paid for interest	$ 1,368	$ 2,813