Segment And Geographic Information (Schedule Of Net Revenues By Geographic Location) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended												12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	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, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues	$ 37,151	$ 37,069	$ 34,690	$ 35,731	$ 35,457	$ 36,250	$ 33,520	$ 35,536	$ 32,800	$ 33,429	$ 33,188	$ 32,301	$ 144,641	$ 140,763	$ 131,718
U.S. [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues													110,533	109,325	103,804
International [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues													$ 34,108	$ 31,438	$ 27,914