Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 15,412	$ 48,409
Short-term investments	14,401	6,610
Accounts receivable, net of allowance for doubtful accounts of $913 and $911 as of December 31, 2013 and 2012, respectively	22,116	24,185
Prepaid expenses and other current assets	5,516	1,427
Deferred tax assets	555	862
Total current assets	58,000	81,493
Property and equipment, net	9,457	8,817
Long-term investments	3,959	21,321
Goodwill	94,171	93,792
Intangible assets, net of accumulated amortization	4,958	7,043
Deferred tax assets	5,873	7,457
Other assets	564	269
Total assets	176,982	220,192
Current liabilities:
Accounts payable	2,686	2,907
Accrued expenses and other current liabilities	3,300	3,535
Accrued compensation expenses	1,175	1,233
Income taxes payable		1,186
Deferred revenue	7,097	5,985
Total current liabilities	14,258	14,846
Long-term liabilities:
Deferred rent	2,980	3,250
Deferred tax liabilities	745	702
Contingent consideration	928	1,180
Other liabilities	1,009	900
Total liabilities	19,920	20,878
Commitments and contingencies (Note 9)
Stockholders' equity:
Preferred stock, 5,000,000 shares authorized; no shares issued or outstanding
Common stock, $0.001 par value per share, 100,000,000 shares authorized; 47,648,102 shares issued and 31,983,440 shares outstanding at December 31, 2013; 45,461,257 shares issued and 39,507,439 shares outstanding at December 31, 2012	48	46
Treasury stock, 15,664,662 and 5,953,818 shares at December 31, 2013 and 2012, respectively, at cost	(83,862)	(35,810)
Additional paid-in capital	270,726	263,426
Accumulated other comprehensive income (loss)	199	(136)
Accumulated deficit	(30,049)	(28,212)
Total stockholders' equity	157,062	199,314
Total liabilities and stockholders' equity	$ 176,982	$ 220,192