Consolidated Statements of Cash Flow (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Net income	$ 70,569,000	$ 71,378,000	$ 59,019,000
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation and amortization	9,155,000	7,514,000	6,038,000
Provision for doubtful accounts	442,000	976,000	1,143,000
Provision for deferred taxes	(4,760,000)	(5,727,000)	(2,753,000)
Unrealized foreign exchange (gain)/losses on forward contracts	0	2,346,000	(1,304,000)
Unrealized foreign exchange (gain)/losses	443,000	(5,795,000)	(598,000)
Unrealized gain on put option	(191,000)	(537,000)	(6,059,000)
Share-based compensation	2,083,000	2,205,000	1,850,000
Debt discount amortization on convertible debt	39,000	21,000	327,000
Reduction of acquisition earn-out contingent liability	(699,000)	(2,847,000)	(1,500,000)
Changes in current assets and liabilities, net of acquisitions:
Accounts receivable	(2,023,000)	(2,903,000)	(3,018,000)
Other assets	(371,000)	1,647,000	(955,000)
Accounts payable and accrued expenses	730,000	1,525,000	(356,000)
Accrued payroll and related benefits	(594,000)	(532,000)	165,000
Deferred rent	(132,000)	(261,000)	(125,000)
Other liabilities	(2,384,000)	836,000	(61,000)
Deferred revenue	(12,000)	796,000	(35,000)
Net cash provided by operating activities	72,295,000	70,642,000	51,778,000
Cash flows from investing activities:
Purchases of marketable securities	(785,000)	(3,098,000)	(11,507,000)
Maturities of marketable securities	1,466,000	7,600,000	7,006,000
Capital expenditures	(1,965,000)	(2,829,000)	(1,754,000)
Net cash used in investing activities	(63,375,000)	(13,320,000)	(24,406,000)
Cash flows from financing activities:
Proceeds from / (Repayment) to line of credit, net	6,090,000	6,750,000	1,900,000
Proceeds from term loan	45,000,000	16,250,000	10,157,000
Proceeds from the issuance of note payable	161,000	0	0
Principal payments on term loan obligation	(19,125,000)	(6,407,000)	(5,000,000)
Repurchase of common stock	(18,374,000)	(63,659,000)	(10,650,000)
Settlement on conversion of convertible debt	0	(6,761,000)	(22,521,000)
Payments of long term debt	(600,000)	0	0
Payments for capital lease obligations	(284,000)	(300,000)	(804,000)
Excess tax benefit from share-based compensation	1,044,000	644,000	1,001,000
Proceeds from exercise of common stock options	1,020,000	51,000	1,236,000
Forfeiture of certain shares to satisfy exercise costs and the recipients income tax obligations related to stock options exercised and restricted stock vested	(992,000)	0	0
Dividends paid	(7,034,000)	(1,461,000)	0
Net cash provided (used) by financing activities	6,906,000	(54,893,000)	(24,681,000)
Effect of foreign exchange rates on cash and cash equivalents	(3,073,000)	(2,130,000)	1,479,000
Net change in cash and cash equivalents	12,753,000	299,000	4,170,000
Cash and cash equivalents at the beginning of the year	23,696,000	23,397,000	19,227,000
Cash and cash equivalents at the end of the year	36,449,000	23,696,000	23,397,000
Supplemental disclosures of cash flow information:
Interest paid	1,350,000	710,000	526,000
Income taxes paid	8,590,000	3,796,000	2,396,000
BSI [Member]
Cash flows from investing activities:
Payments to Acquire Businesses, Net of Cash Acquired	(992,000)	0
Taimma [Member]
Cash flows from investing activities:
Payments to Acquire Businesses, Net of Cash Acquired	(5,003,000)	0
Fintechnix [Member]
Cash flows from investing activities:
Payments to Acquire Businesses, Net of Cash Acquired	(4,713,000)	0
Planetsoft [Member]
Adjustments to reconcile net income to cash provided by operating activities:
Unrealized gain on put option	(191,000)
Cash flows from investing activities:
Payments to Acquire Businesses, Net of Cash Acquired	(35,078,000)	0
TriSystems [Member]
Cash flows from investing activities:
Payments to Acquire Businesses, Net of Cash Acquired	(9,277,000)	0
Curepet, Inc. [Member]
Cash flows from investing activities:
Payments to Acquire Investments	(2,000,000)	0	0
ADAM
Cash flows from investing activities:
Investment, net of cash acquired	0	3,529,000	0
MCN
Cash flows from investing activities:
Investment, net of cash acquired	(1,537,000)	(381,000)	(2,931,000)
Trades Monitor [Member]
Cash flows from investing activities:
Investment, net of cash acquired	0	0	(2,749,000)
Connective Technologies [Member]
Cash flows from investing activities:
Investment, net of cash acquired	0	0	(1,337,000)
USIX [Member]
Cash flows from investing activities:
Investment, net of cash acquired	(1,466,000)	0	(7,131,000)
E Trek [Member]
Cash flows from investing activities:
Investment, net of cash acquired	0	0	(1,011,000)
Health Connect Systems [Member]
Cash flows from investing activities:
Investment, net of cash acquired	(2,000,000)	(17,945,000)	0
ConfirmNet
Cash flows from investing activities:
Investment, net of cash acquired	0	(184,000)	(2,975,000)
Periculum [Member]
Cash flows from investing activities:
Investment, net of cash acquired	0	0	(6,000)
Facts [Member]
Cash flows from investing activities:
Investment, net of cash acquired	$ (25,000)	$ (12,000)	$ (11,000)