Earnings (Loss) Per Common Share (Narrative) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	9 Months Ended
Sep. 30, 2011	Nov. 30, 2006
Average stock considered as issuable under the treasury	0.8
0.875% Convertible Notes Due 2013 [Member]
Weighted average conversion price per share	$ 50.36
Strike price of warrants, per share	$ 76.00
Interest rate on senior convertible notes	0.875%	7.35%
1.00% Senior Convertible Notes Due 2012 [Member]
Weighted average conversion price per share	$ 83.93
Interest rate on senior convertible notes	1.00%
Subordinated Convertible Notes Due 2029 [Member]
Weighted average conversion price per share	$ 36.75

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of convertible debt securities using the if-converted method.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 128

-Paragraph 26, 27, 28

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 260

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 260

-SubTopic 10

-Section 45

-Paragraph 40

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6920599&loc=d3e1930-109256

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