Goodwill and Other Intangible Assets (Schedule of Goodwill) (Details) (USD $) In Thousands, unless otherwise specified							3 Months Ended
	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2012 Blaze Acquisition [Member]	Feb. 07, 2012 Blaze Acquisition [Member]	Jun. 30, 2012 Cotendo Acquisition [Member]	Sep. 30, 2011 Cotendo Acquisition [Member]	Mar. 31, 2012 Cotendo Acquisition [Member]	Mar. 06, 2012 Cotendo Acquisition [Member]	Sep. 30, 2012 FastSoft [Member]	Sep. 13, 2012 FastSoft [Member]
Goodwill [Line Items]
Goodwill	$ 721,601	$ 709,668	$ 709,628	$ 452,914
Business acquisition purchase price allocation for goodwill					15,068	15,100			241,646	241,386	12,233	12,200
Business acquisition, purchase price adjustment							$ 40	$ (300)