Operating Segment Information (Schedule Of Revenues From External Customers By Geographic Regions) (Details) (USD $) In Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Operating Segment Information [Abstract]
United States	$ 47,463	$ 44,638	$ 121,827	$ 125,261
International	58,716	63,667	188,911	208,542
Total revenues from external customers	$ 106,179	$ 108,305	$ 310,738	$ 333,803

Revenues from external customers attributed to all foreign countries in total from which the entity derives revenues.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 131

-Paragraph 38

-Subparagraph a(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 280

-SubTopic 10

-Section 50

-Paragraph 41

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e9038-108599

Name:	us-gaap_EntityWideDisclosureOnGeographicAreasRevenueFromExternalCustomersAttributedToForeignCountries
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration