Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Cash flows from operating activities
Net income	$ 60,069	$ 47,704	$ 31,428
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	8,233	6,781	6,350
Stock-based compensation expense	8,385	6,859	8,969
Deferred taxes	(643)	16,129	15,767
Provision for bad debts	519	1,177	602
Other	685		(411)
Changes in operating assets and liabilities:
Decrease (increase) in accounts receivable	4,607	(11,665)	(3,134)
Decrease (Increase) in prepaid expenses and other assets	412	(4,074)	57
Increase in accrued employee compensation	491	1,634	2,634
(Decrease) increase in deferred revenue	(462)	755	309
(Decrease) increase in accounts payable, accrued expenses and other liabilities	(714)	178	1,575
Net cash provided by operating activities	81,582	65,478	64,146
Securities available-for-sale:
Proceeds from sales	23,663		15,377
Proceeds from maturities	18,313	27,419	49,988
Purchases	(16,543)	(32,302)	(66,008)
Securities and cash (provided) received as collateral	(43)	3,532	32
Purchases of furniture, equipment and leasehold improvements	(5,153)	(3,160)	(5,205)
Capitalization of software development costs	(5,207)	(4,065)	(1,904)
Net cash provided by (used in) investing activities	15,030	(8,576)	(7,720)
Cash flows from financing activities
Cash dividend on common stock and Series B Preferred Stock	(64,041)	(13,683)	(10,630)
Exercise stock options	8,525	6,807	6,761
Excess tax benefits from stock-based compensation	14,775	7,305	1,619
Withholding tax payments on restricted stock vesting and stock option exercises	(20,003)	(4,415)	(2,055)
Repurchase of common stock	(75,133)	(6,935)	(30,000)
Other	(298)	(278)	456
Net cash (used in) financing activities	(136,175)	(11,199)	(33,849)
Effect of exchange rate changes on cash and cash equivalents	(1,149)	(1,077)	(924)
Cash and cash equivalents
Net (decrease) increase for the period	(40,712)	44,626	21,653
Beginning of period	169,620	124,994	103,341
End of period	128,908	169,620	124,994
Cash paid during the year
Cash paid for income taxes	15,102	10,177	2,228
Non-cash activity
Conversion of Series B Preferred Stock to common stock		30,315
Conversion of common stock non-voting to common stock voting	$ 15,880