Business Acquisitions (Pro Forma Results of Operations) (Details) (OptionsXpress Holdings, Inc. [Member], USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2011
OptionsXpress Holdings, Inc. [Member]
Business Acquisition [Line Items]
Net revenues	$ 4,857
Net income	$ 896
Basic EPS	$ 0.71
Diluted EPS	$ 0.71

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The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(2)-(3)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

+ Details

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

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