Condensed Consolidated Statements of Cash Flows - Unaudited - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Operating activities:
Cash provided by (used in) operating activities - continuing operations	$ 23,155	$ (5,358)
Cash used in operating activities - discontinued operations	(4,131)	(12,778)
Net cash provided by (used in) operating activities	19,024	(18,136)
Investing activities:
Purchases of investments	(427)	(383)
Proceeds from sale of investments	2,474	30
Purchases of property, plant and equipment	(44)	(39)
Proceeds from sale of property, plant and equipment	258
Cash provided by (used in) investing activities - continuing operations	2,261	(392)
Cash provided by (used in) investing activities - discontinued operations	5,892	(675)
Net cash provided by (used in) investing activities	8,153	(1,067)
Financing activities:
Payment of withholding taxes on exercise of restricted stock units	(122)
Purchases of treasury stock	(184)
Cash used in financing activities - continuing operations	(306)	0
Cash provided by (used in) financing activities - discontinued operations	(754)	2,307
Net cash provided by (used in) financing activities	(1,060)	2,307
Increase (decrease) in cash and cash equivalents	26,117	(16,896)
Cash and cash equivalents, beginning of the period	60,980	57,400
Cash and cash equivalents, end of the period	87,097	40,504
Less cash and cash equivalents of discontinued operations at the end of the period	34,270	30,321
Cash and cash equivalents of continuing operations, end of the period	52,827	10,183
Unpaid liability incurred for development costs		395
Issuance of common stock for vested restricted stock units	$ 1,476	$ 98