Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Operating Activities:
Net income (loss)	$ (1,837)	$ 4,024	$ 4,689
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Depreciation and amortization	6,046	6,630	6,735
Provision for bad debt	564	827	316
Amortization of investment premiums	466	927	983
Stock-based compensation	5,585	5,267	7,469
Deferred tax provision (benefit)	1,554	231	(1,374)
Excess tax benefit - stock options	(506)	(422)	(2,054)
Changes in operating assets and liabilities, net of businesses acquired:
Accounts receivable	1,496	1,860	(1,661)
Prepaid expenses and other current assets	(524)	384	(760)
Other assets	(314)	(54)	(81)
Accounts payable	(239)	(144)	(853)
Income taxes payable	(5,004)	321	3,174
Accrued expenses and other current liabilities	412	(1,421)	1,921
Accrued compensation expenses	(17)	57	(779)
Deferred revenue	1,112	374	(1,210)
Other liabilities	(519)	(225)	(657)
Net cash provided by operating activities	8,275	18,636	15,858
Investing activities:
Purchases of property and equipment, and other assets	(4,477)	(4,150)	(4,481)
Purchases of investments	(16,433)	(21,373)	(38,211)
Proceeds from sales and maturities of investments	25,555	29,954	17,370
Acquisition of businesses, net of cash acquired		(1,117)	(2,049)
Net cash provided by (used in) investing activities	4,645	3,314	(27,371)
Financing activities:
Purchase of treasury shares	(47,912)	(467)
Excess tax benefit - stock options	506	422	2,054
Tender offer fees	(140)
Shelf registration fees		(69)
Proceeds from exercise of stock options	1,560	766	2,817
Net cash (used in) provided by financing activities	(45,986)	652	4,871
Effect of exchange rate changes on cash and cash equivalents	69	21	(156)
Net (decrease) increase in cash and cash equivalents	(32,997)	22,623	(6,798)
Cash and cash equivalents at beginning of period	48,409	25,786	32,584
Cash and cash equivalents at end of period	15,412	48,409	25,786
Supplemental disclosure of cash flow information:
Cash paid for interest
Cash paid for income taxes	2,834	3,662	4,153
Supplemental disclosure of non-cash investing activities:
Accrual for contingent consideration and cash to be paid in connection with an acquisition		$ 1,715	$ 1,405