Income Taxes (Details) (USD $)	3 Months Ended	6 Months Ended
Mar. 31, 2010	Jun. 30, 2011	Jun. 30, 2010
Components of effective tax rate
Estimated annual effective tax rate		29.00%	30.60%
Discrete tax adjustments		(12.70%)	2.00%
Effective tax rate		16.30%	32.60%
Income Taxes (Textuals) [Abstract]
Decrease in unrecognized tax benefits resulting from resolution of foreign tax issue	$ 179,000,000
Decrease in unrecognized tax benefits resulting from Australian Tax Office audit		197,000,000
Discrete tax charge reflecting health care reform legislation	21,881,000
Discrete non-cash tax benefit resulting from Australian Tax Office audit		$ 165,927,000

Decrease in unrecognized tax benefits resulting from resolution of foreign tax issue.

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Discrete non-cash tax benefit resulting from Australian Tax Office audit.

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Discrete tax charge reflecting health care reform legislation.

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Estimated annual effective tax rate.

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Income Taxes textuals.

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Possible reduction in unrecognized tax benefits resulting from Australian Tax Office audit.

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A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(2))
-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 47
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph h
-Subparagraph 2
-Article 4

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 13
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- Definition

The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to all other items not otherwise listed in the existing taxonomy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32698-109319

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-Name Accounting Standards Codification
-Topic 740
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-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I)
-URI http://asc.fasb.org/extlink&oid=6889476&loc=d3e330036-122817

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