Long Lived Assets (Details 3) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Client contracts
Summary of aggregate amortization
Total amortization expense	$ 23,545	$ 28,780	$ 27,943
Client contracts | Investments in client contracts
Summary of aggregate amortization
Total amortization expense	6,181	7,591	7,521
Client contracts | Capitalized costs
Summary of aggregate amortization
Total amortization expense	2,365	4,172	3,296
Client contracts | Acquired client contracts
Summary of aggregate amortization
Total amortization expense	14,999	17,017	17,126
Software
Summary of aggregate amortization
Total amortization expense	11,854	12,685	11,232
Software | Acquired software
Summary of aggregate amortization
Total amortization expense	4,221	5,700	5,595
Software | Internal use software
Summary of aggregate amortization
Total amortization expense	$ 7,633	$ 6,985	$ 5,637