Stock-Based Compensation Plans - Additional Information (Detail) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued under ESPP			68,079	60,762
Incentive plan, percentage of options expected to vest over the vesting period	93.40%		93.40%
Incentive plan, weighted-average grant date fair value of stock options granted			$ 9.02	$ 8.02
Incentive plan, total intrinsic value of stock options exercised			$ 6,600,000	$ 6,000,000
Dividend yield		0.00%	0.00%	0.00%
Dividend paid			$ 0
Stock-based compensation expenses	4,400,000	3,800,000	9,188,000	7,724,000
Stock-based compensation expenses tax benefits	1,700,000	1,400,000	3,500,000	2,900,000
Proceeds from exercises of stock options			4,117,000	5,583,000
Actual tax benefit realized from tax deductions of option exercises			2,500,000	2,300,000
Employee Stock Purchase Plan 1999
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock reserved for issuance	4,500,000		4,500,000
Permitted designation for purchase of common stock under ESPP			Participating employees are permitted to designate up to the lesser of $25,000 or 10% of their annual base compensation for the purchase of common stock under the ESPP. Purchases under the ESPP are made one calendar month after the end of each fiscal quarter.
Employee participating annual base compensation designated for purchase of common stock, amount	25,000		25,000
Employee participating annual base compensation designated for purchase of common stock, percent	10.00%		10.00%
Price of common stock purchased under ESPP, description			The price for shares of common stock purchased under the ESPP is 85% of the stock's fair market value on the last business day of the three-month participation period.
Price of common stock purchased under ESPP, percent			85.00%
Restricted share awards (RSAs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares awards, shares vested			5,802
Restricted shares withheld to pay employees' portion of minimum payroll withholding taxes			1,908
Unrecognized compensation costs	3,200,000		3,200,000
Unrecognized compensation costs, weighted-average recognition periods			1 year 2 months 12 days
Restricted share awards (RSAs) | S1 Corporation
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted requisite service period			4 years
Original grant date			Nov. 09, 2011
Restricted share awards, vesting increments on anniversary dates of grants			25.00%
Vesting percentage if employee is terminated without cause within 12 months from acquisition date	100.00%		100.00%
LTIP Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares awards, shares vested			635,643
Restricted shares withheld to pay employees' portion of minimum payroll withholding taxes			228,279
Unrecognized compensation costs	16,900,000		16,900,000
Unrecognized compensation costs, weighted-average recognition periods			2 years 1 month 6 days
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs	$ 9,800,000		$ 9,800,000
Unrecognized compensation costs, weighted-average recognition periods			2 years 1 month 6 days