CONSOLIDATED STATEMENT OF CASH FLOWS (USD $) In Thousands	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010
Operating activities:
Net income	$ 22,239	$ 16,691
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	9,805	7,307
Stock-based compensation expense	3,966	3,428
Deferred income taxes	839	(782)
Decrease in allowance for doubtful debts	(74)
Change in fair value of contingent consideration	399
Loss on disposal of fixed assets	2	21
Changes in assets and liabilities:
(Increase)/Decrease in accounts receivable	(5,597)	831
(Increase)/Decrease in prepaid expenses	(1,006)	(134)
(Increase)/Decrease in prepaid income taxes	141	(624)
(Increase)/ Decrease in other current assets	11	(58)
(Increase)/Decrease in other assets	(154)	682
Decrease in accounts payable, accrued expenses and other liabilities	(6,377)	(5,058)
Net cash provided by operating activities	24,194	22,304
Investing activities:
Investment in certificate of deposit	(4,809)
Purchases of property and equipment	(8,986)	(5,430)
Purchase of building and land		(9,886)
Acquisition of AMG-SIU	161	(12,795)
Acquisition of Verify Solutions	(500)
Investment in capitalized software	(1,060)	(1,006)
Net cash used in investing activities	(15,194)	(29,117)
Financing activities:
Proceeds from exercise of stock options	7,763	3,713
Payments of tax withholdings on behalf of employees for net-share settlement for stock-based compensation	(903)
Excess tax benefit from exercised stock options	6,960	4,972
Net cash provided by financing activities	13,820	8,685
Net increase in cash and cash equivalents	22,820	1,872
Cash and cash equivalents at beginning of period	94,836	64,863
Cash and cash equivalents at end of period	117,656	66,735
Supplemental disclosure of cash flow information:
Cash paid for income taxes	7,027	7,667
Cash paid for interest	47	23
Supplemental disclosure of noncash investing activities:
Accrued property and equipment purchases	1,012	502
Accrued acquisition related contingent consideration		$ 2,573