Pro Forma Financial Information (re: 2013 and 2012 acquisitions) (Details) (USD $)	3 Months Ended												12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Business Acquisition, Pro Forma Information [Abstract]
Revenue, As Reported	$ 50,847,000	$ 50,293,000	$ 51,004,000	$ 52,566,000	$ 54,023,000	$ 53,804,000	$ 47,716,000	$ 43,827,000	$ 44,050,000	$ 42,602,000	$ 42,267,000	$ 40,050,000	$ 204,710,000	$ 199,370,000	$ 168,969,000
Net Income, As Reported	15,245,000	13,143,000	13,542,000	17,344,000	18,745,000	18,072,000	18,067,000	15,685,000	17,330,000	16,536,000	22,348,000	15,164,000	59,274,000	70,569,000	71,378,000
Basic EPS, As Reported (in dollars per share)	$ 0.40	$ 0.35	$ 0.36	$ 0.47	$ 0.50	$ 0.49	$ 0.49	$ 0.43	$ 0.48	$ 0.44	$ 0.57	$ 0.40	$ 1.58	$ 1.91	$ 1.89
Diluted EPS, As Reported (in dollars per share)	$ 0.40	$ 0.34	$ 0.35	$ 0.45	$ 0.48	$ 0.46	$ 0.47	$ 0.40	$ 0.44	$ 0.41	$ 0.53	$ 0.37	$ 1.53	$ 1.80	$ 1.75
Effect of Exchange Rate on Revenue													(3,800,000)	(1,200,000)	4,200,000
Parent, Planetsoft, BSI, Taimma, Fintechnix, TriSystems , Qatarlyst Combined [Member]
Business Acquisition, Pro Forma Information [Abstract]
Increase (decrease) in unaudited pro forma revenue													(9,400,000)
Parent, Qatarlyst [Member]
Business Acquisition, Pro Forma Information [Abstract]
Revenue, Pro forma													205,619,000
Net Income, Pro Forma													57,966,000
Basic EPS, Pro Forma (in dollars per share)													$ 1.54
Diluted EPS, Pro Forma (in dollars per share)													$ 1.50
Parent, ADAM, Planetsoft, BSI, Taimma, Fintechnix, TriSystems , Combined [Member] [Domain]
Business Acquisition, Pro Forma Information [Abstract]
Revenue, Pro forma														215,004,000
Net Income, Pro Forma														57,008,000
Basic EPS, Pro Forma (in dollars per share)														$ 1.54
Diluted EPS, Pro Forma (in dollars per share)														$ 1.45
Increase (decrease) in unaudited pro forma revenue, percentage													(4.40%)
Increase (decrease) in reported revenue													$ 5,300,000
Increase (decrease) in reported revenue, percentage													2.70%