Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash flows from operating activities
Net income	$ 96,037	$ 74,806	$ 76,016
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	18,542	17,379	13,051
Stock-based compensation expense	12,519	9,769	8,879
Deferred taxes	(2,424)	(374)	(1,331)
Gain on the sale of discontinued operations			(7,642)
Other	2,049	1,725	(296)
Changes in operating assets and liabilities:
Decrease (increase) in accounts receivable	(6,748)	827	(1,714)
Decrease (increase) in prepaid expenses and other assets	(2,662)	3,344	(1,846)
Increase in accrued employee compensation	3,986	1,309	4,010
(Decrease) increase in income and other tax liabilities	(941)	2,365	2,959
(Decrease) in deferred revenue	(153)	(248)	(1,571)
(Decrease) increase in accounts payable, accrued expenses and other liabilities	(9)	(950)	364
Net cash provided by operating activities	120,196	109,952	90,879
Cash flows from investing activities
Acquisition of business, net of cash acquired			(37,827)
Cash proceeds from the sale of discontinued operations, net of cash sold			9,346
Securities available-for-sale:
Proceeds from sales			30,900
Proceeds from maturities	35,248	17,574	12,515
Purchases	(57,175)	(16,423)	(60,755)
Purchases of furniture, equipment and leasehold improvements	(4,795)	(4,627)	(15,337)
Capitalization of software development costs	(10,589)	(10,160)	(7,945)
Other	(642)	611	(18)
Net cash (used in) investing activities	(37,953)	(13,025)	(69,121)
Cash flows from financing activities
Cash dividend on common stock	(29,534)	(23,941)	(19,837)
Exercise of stock options	1,824	2,511	3,039
Withholding tax payments on restricted stock vesting and stock option exercises	(4,496)	(5,020)	(5,001)
Excess tax benefits from stock-based compensation	4,310	4,243	5,032
Repurchases of common stock	(23,158)	(37,974)
Other		(42)	(307)
Net cash (used in) financing activities	(51,054)	(60,223)	(17,074)
Effect of exchange rate changes on cash and cash equivalents	(385)	(471)	(901)
Cash and cash equivalents
Net increase for the period	30,804	36,233	3,783
Beginning of period	168,924	132,691	128,908
End of period	199,728	168,924	132,691
Cash paid during the year
Cash paid for income taxes	$ 50,875	$ 33,627	30,768
Liabilities assumed in connection with the Xtrakter acquisition:
Fair value of assets acquired			44,791
Cash paid for the capital stock			(37,827)
Liabilities assumed			$ 6,964