Auction rate securities, at Fair Value

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- Definition

Financial Instruments Fair Value Assumptions Weighted Average Discount Rate

+ Details

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- Definition

The difference between the carrying value and the sale price of an investment. A gain would be recognized when the sale price of the investment is greater than the carrying value of the investment. This element refers to the Gain included in earnings and not to the cash proceeds of the sale.

+ Details

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- Definition

Investment Maturity Period

+ Details

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- Details

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- Definition

Discussion of whether the debt instrument is secured or unsecured, and, if secured, a description of the collateral and guarantees required or provided.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 2, 4

+ Details

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- Definition

Aggregate notional amount of all derivatives designated as cash flow hedging instruments. The notional amount relates to a number of currency units, shares, bushels, pounds, or other units specified in a derivative instrument.

+ Details

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- Definition

Investments which are intended to be sold in the short term (usually less than one year or the normal operating cycle, whichever is longer) including trading securities, available-for-sale securities, held-to-maturity securities, and other short-term investments not otherwise listed in the existing taxonomy.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Subparagraph g

-Article 7

+ Details

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Fair Value of Financial Assets and Liabilities - Additional Information (Detail) (USD $)	9 Months Ended	12 Months Ended	9 Months Ended			3 Months Ended
	Sep. 30, 2011	Dec. 31, 2010	Sep. 30, 2011 Lower Limit Variable Rate Demand Note	Sep. 30, 2011 Upper Limit Variable Rate Demand Note	Sep. 30, 2011 Variable Rate Demand Note	Jun. 30, 2011 VMware	Sep. 30, 2011 Foreign Sovereign Debt Securities
Percentage of Available For Sale Securities Debt Securities							6.00%
Aggregate notional amount of interest rate swap contracts designated as cash flow hedges		$ 900,000,000
The rate used for the discount margin to determine the estimated fair value of investment in auction rate securities	2.00%	1.00%
Auction rate securities that have partial guarantees by the U.S. government, market value	18,400,000
Percentage of Loans collateralized auction rate securities	FFELP guarantees at least 95% of the loans which collateralize the auction rate securities.
Short term investment	1,635,533,000	1,256,175,000			30,600,000
Gain on sale of strategic investment						$ 56,000,000
Contractual maturity period	P90D	P90D	2013	2045