Stock-Based Compensation (Narrative) (Details) (USD $) In Thousands, except Share data	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Stock-Based Compensation
Proceeds from stock option exercises	$ 7,239	$ 23,172
Stock option exercises and deferred stock	140,739
Issuance of treasury stock - deferred stock conversions	3,464

The cash inflow associated with the amount received from holders exercising their stock options.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 18

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph i

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 19
-Subparagraph a

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