CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Cash Flows [Abstract]
Net income (loss)	$ (16,305)	$ (36,550)	$ (81,847)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation and amortization	2,936	7,057	10,410
Stock-based compensation	3,675	5,424	4,698
Equity in net loss of Napster	3,991	6,533	14,521
Lease exit and related charges	0	2,239	2,501
Deferred income taxes, net	(3,871)	130	(1,558)
Loss (gain) on investments, net	(4,500)	(8,473)	159
Realized translation loss (gain)	0	272	(264)
Fair value of warrants granted in 2015 and 2017, net of subsequent mark to market adjustments in 2017, 2016 and 2015	(216)	280	(1,053)
Net change in certain operating assets and liabilities:
Trade accounts receivable	(5,845)	(129)	(8,236)
Deferred costs, prepaid expenses and other assets	2,146	964	2,606
Accounts payable	(599)	1,571	(465)
Accrued and other liabilities	(2,762)	(3,646)	(10,454)
Net cash provided by (used in) operating activities	(21,350)	(24,328)	(68,982)
Cash flows from investing activities:
Purchases of equipment, software, and leasehold improvements	(734)	(2,438)	(1,319)
Proceeds from sale of equity and other investments	0	4,967	459
Purchases of short-term investments	(13,905)	(75,766)	(72,136)
Proceeds from sales and maturities of short-term investments	48,457	84,249	78,775
Decrease in restricted cash equivalents and investments	300	190	110
Acquisitions	0	(150)	(161)
Advance to Napster	(1,500)	(3,500)	(5,000)
Repayment from Napster	0	0	5,000
Proceeds from the sale of Slingo and social casino business	4,500	4,000	10,000
Net cash provided by (used in) investing activities	37,118	11,552	15,728
Cash flows from financing activities:
Proceeds from issuance of common stock (stock options and stock purchase plan)	239	535	426
Tax payments from shares withheld upon vesting of restricted stock	(356)	(880)	(85)
Net cash provided by (used in) financing activities	(117)	(345)	341
Effect of exchange rate changes on cash and cash equivalents	1,824	(473)	(3,025)
Net increase (decrease) in cash and cash equivalents	17,475	(13,594)	(55,938)
Cash and cash equivalents, beginning of year	33,721	47,315	103,253
Cash and cash equivalents, end of year	51,196	33,721	47,315
Supplemental disclosure of cash flow information:
Cash received from income tax refunds	420	534	1,102
Cash paid for income taxes	1,244	2,072	1,491
Non-cash investing activities:
Increase (decrease) in accrued purchases of equipment, software, and leasehold improvements	(86)	26	(150)
Acquisition of intangible assets	$ 0	$ 0	$ 102