Segment Information Reportable Segment Information (Reconciliation of Total Segment Operating Income to Consolidated Operating Income) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Segment Reporting Information [Line Items]
Total revenues	$ 178,701	$ 153,018	$ 515,992	$ 431,886
Direct Costs By Segment	114,587	96,713	338,563	273,914
Income from operations	55,733	46,478	146,329	132,900
Global Operating Costs	8,428	9,882	31,269	25,254
Business Cloud Services Segment [Member]
Segment Reporting Information [Line Items]
Total revenues	126,436	109,855	369,685	317,208
Direct Costs By Segment	69,617	60,841	213,518	176,609
Income from operations	56,819	49,014	156,167	140,599
Digital Media Segment [Member]
Segment Reporting Information [Line Items]
Total revenues	52,312	43,218	146,476	114,860
Direct Costs By Segment	44,970	35,872	125,045	97,305
Income from operations	7,342	7,346	21,431	17,555
Intersegment Elimination [Member]
Segment Reporting Information [Line Items]
Total revenues	(47)	(55)	(169)	(182)
Operating Segments [Member]
Segment Reporting Information [Line Items]
Income from operations	$ 64,161	$ 56,360	$ 177,598	$ 158,154