Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Cash flows from operating activities:
Net income (loss)	$ 40,155		$ (7,197)	[1]	$ (3,430)	[1]
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation and amortization of property and equipment	584		654	[1]	1,128	[1]
Amortization of intangibles	79		49	[1]	39	[1]
Stock-based compensation	4,644		3,146	[1]	3,555	[1]
Allowance (recovery) for doubtful accounts	8		113	[1]	(22)	[1]
Loss on disposal of equipment	11		27	[1]	(6)	[1]
Gain on sales of discontinued operations	0		(153)	[1]	(61)	[1]
Changes in operating assets and liabilities:
Accounts and other receivables	1,272		(504)	[1]	(567)	[1]
Inventories	141		282	[1]	(17)	[1]
Deferred income taxes	(36,850)		0	[1]	0	[1]
Prepaid expenses and other current assets	16		(227)	[1]	3,342	[1]
Other assets	(152)		(54)	[1]	(116)	[1]
Accounts payable	341		8	[1]	(47)	[1]
Accrued compensation and other current liabilities	2,788		(717)	[1]	(917)	[1]
Deferred revenue	8,206		(3,194)	[1]	(3,574)	[1]
Other long-term liabilities	(91)		374	[1]	(266)	[1]
Net cash provided by (used in) operating activities	21,152		(7,393)	[1]	(959)	[1]
Cash flows provided by (used in) investing activities:
Purchases of available-for-sale investments	(94,931)		(43,944)	[1]	(48,905)	[1]
Proceeds from maturities of available-for-sale investments	77,000		54,000	[1]	49,000	[1]
Additions to intangibles	0		(100)	[1]	0	[1]
Purchases of property and equipment	(234)		(1,000)	[1]	(169)	[1]
Proceeds from sales of discontinued operations	0		250	[1]	100	[1]
Net cash provided by (used in) investing activities	(18,165)		9,206	[1]	26	[1]
Cash flows provided by (used in) financing activities:
Issuance of common stock under employee stock purchase plan	198		122	[1]	145	[1]
Exercise of stock options	6,393		1,046	[1]	2,293	[1]
Purchases of treasury stock	0		(5,721)	[1]	(6,450)	[1]
Net cash provided by (used in) financing activities	6,591		(4,553)	[1]	(4,012)	[1]
Net increase (decrease) in cash and cash equivalents	9,578		(2,740)	[1]	(4,945)	[1]
Cash and cash equivalents:
Beginning of year	4,558	[1]	7,298	[1]	12,243	[1]
End of year	14,136		4,558	[1]	7,298	[1]
Supplemental disclosure of cash flow information:
Cash paid (received) for taxes	18		21	[1]	(3,302)	[1]
Supplemental disclosure of noncash operating, investing, and financing activities:
Amounts accrued for property and equipment	24		0	[1]	775	[1]
Release of Restricted Stock Units and Awards under company stock plan	$ 3,482		$ 1,298	[1]	$ 1,323	[1]

[1] See Note 1 "Significant Accounting Policies - Intangible Assets" of Notes to Consolidated Financial Statements.