Basis Of Presentation (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Revenue	$ 89,465	$ 85,676	$ 176,117	$ 159,060
Net earnings	31,188	28,514	59,727	59,449
Basic earnings per share	$ 0.68	$ 0.63	$ 1.28	$ 1.31
Diluted earnings per share	$ 0.67	$ 0.61	$ 1.27	$ 1.27
Remaining Service Obligations To eFax Customers [Member]
Revenue				10,300
Net earnings				$ 7,600
Basic earnings per share				$ 0.17
Diluted earnings per share				$ 0.16