Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Cash flows from operating activities:
Net income	$ 15,417	$ 17,344
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	2,552	2,452
Benefit for deferred taxes	(441)	(7,538)
Share based compensation	395	511
Provision for doubtful accounts	353	0
Debt discount amortization on convertible debt	10	13
Unrealized foreign exchange (gain) loss	216	9
(Gain) loss on put option	(454)	(81)
Reduction of acquisition earnout accruals	(1,762)	(299)
Changes in assets and liabilities, net of effects from acquisitions:
Accounts receivable	(4,716)	(2,234)
Other assets	576	357
Accounts payable and accrued expenses	(65)	4,719
Accrued payroll and related benefits	1,029	(643)
Deferred revenue	(2)	(350)
Deferred rent	(163)	44
Unrecognized tax benefits, period increase (decrease)	2,133	68
Loss Contingency Accrual, Period Increase (Decrease)	(4,218)	0
Other current liabilities	(56)	(107)
Net cash provided by operating activities	10,804	14,265
Cash flows from investing activities:
Maturities of marketable securities	0	208
Purchases of marketable securities	(10)	0
Capital expenditures	(413)	(345)
Net cash used in investing activities	(420)	(707)
Cash flows from financing activities:
Principal payments of term loan obligation	(2,406)	(4,125)
Repurchases of common stock	(2,234)	0
Excess tax benefit from share-based compensation	(3,200)	0
Proceeds from the exercise of stock options	788	553
Forfeiture of certain shares to satisfy exercise costs and the recipients income tax obligations related to stock options exercised and restricted stock vested	(25)	(564)
Dividend payments	(2,896)	(2,794)
Principal payments of debt obligations	(9)	(12)
Payments of capital lease obligations	(56)	(80)
Net cash provided used in financing activities	(10,038)	(7,022)
Effect of foreign exchange rates on cash	708	20
Net change in cash and cash equivalents	1,054	6,556
Cash and cash equivalents at the beginning of the period	56,674	36,449
Cash and cash equivalents at the end of the period	57,728	43,005
Supplemental disclosures of cash flow information:
Interest paid	208	352
Income taxes paid	3,087	3,548
Curepet, Inc. [Member]
Cash flows from investing activities:
Acquisition of business, net of cash acquired	3	0
USIX [Member]
Cash flows from investing activities:
Investment in acquisition	$ 0	$ (570)