Stock-Based Compensation (Schedule of Other Information about Restricted Share Awards) (Details) (Restricted Share Awards [Member], USD $) In Thousands, unless otherwise specified	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Restricted Share Awards [Member]
Total fair value of awards vested during the period	$ 3,035	$ 843
Pre-tax unrecognized compensation expense, net of estimated forfeitures as of June 30, 2011	$ 3,770
Weighted-average period to be recognized as expense, years	2.2

The total fair value of equity-based awards for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph c(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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration