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Accounting Policies (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended |
--- | --- | ---
Mar. 31, 2014 | Mar. 31, 2013 | Dec. 31, 2013
Variable Interest Entity [Line Items] |  |  |
Assets | $ 2,723 |  | $ 2,888
Liabilities | 2,413 |  | 2,567
Weighted average common shares adjustment related to stock-based compensation | 2.0 | 1.6 |
Anti-dilutive potential common shares related to stock-based compensation plans | 0.6 | 1.5 |
Maturities of short term investments | 3 months |  |
New collateralized loan obligation temporary warehousing entities [Member] |  |  |
Variable Interest Entity [Line Items] |  |  |
Assets | 82 |  |
Liabilities | $ 67 |  |

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