Segment Reporting (Schedule Of Net Revenues Earned On Major Geographical Areas) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Net revenues	$ 374,407	$ 358,857	$ 774,740	$ 725,470
United States [Member]
Net revenues	365,265	343,800	757,103	694,809
Canada [Member]
Net revenues	3,814	6,813	6,066	13,261
United Kingdom [Member]
Net revenues	2,942	6,088	6,832	12,137
Other European [Member]
Net revenues	$ 2,386	$ 2,156	$ 4,739	$ 5,263

Revenues from external customers attributed to the entity's country of domicile.

Reference 1: 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

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 131

-Paragraph 38

-Subparagraph a(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration