Consolidated Statements of Income (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Income Statement [Abstract]
Revenues, net	$ 193,651	$ 146,165
Expenses:
Merchant commissions	13,861	10,393
Processing	29,943	25,579
Selling	11,704	10,175
General and administrative	29,261	23,823
Depreciation and amortization	14,629	11,720
Operating income	94,253	64,475
Other expense, net	292	588
Interest expense, net	3,448	3,563
Total other expense	3,740	4,151
Income before taxes	90,513	60,324
Provision for taxes	25,851	18,245
Net income	$ 64,662	$ 42,079
Earnings per share:
Basic earnings per share	$ 0.80	$ 0.51
Diluted earnings per share	$ 0.77	$ 0.49
Weighted average shares outstanding:
Basic weighted average shares outstanding	81,222	82,565
Diluted weighted average shares outstanding	83,960	85,164