The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

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-Publisher AICPA
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-Paragraph 16, 20
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Interest rate stated in the contractual debt agreement.

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-Name Regulation S-X (SX)
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-Section 02
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-Name Accounting Standards Codification
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Date when the debt instrument is scheduled to be fully repaid, which may be presented in a variety of ways (year, month and year, day, month and year, quarter, etc.).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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Total interest costs incurred during the period that are capitalized.

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The cash inflow from other long-term borrowings not otherwise defined in the taxonomy (with maturities initially due beyond one year or the normal operating cycle of the entity, if longer).

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The cash outflow attributable to repayments of borrowings not otherwise defined in the taxonomy (with maturities initially due after one year or beyond the operating cycle if longer).

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Debt instruments maturity date.

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Debt (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended		1 Months Ended												1 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Feb. 28, 2010 Notes Due In February 2015 [Member]	Feb. 28, 2010 Notes Due In February 2020 [Member]	Feb. 28, 2010 Notes Issued In February 2010 [Member]	Mar. 31, 2010 Senior Notes Due In June 2015 [Member]	Apr. 30, 2011 Industrial Revenue Bonds Tax Exempt Refunding Bonds [Member]	Apr. 30, 2010 Industrial Revenue Bonds Tax Exempt Refunding Bonds [Member]	Apr. 30, 2011 Tax Exempt Revenue Refunding Bonds Series 1997A [Member]	Apr. 30, 2010 Tax Exempt Revenue Refunding Bonds Series 1997A [Member]	Apr. 30, 2011 Tax Exempt Revenue Refunding Bonds Series 1997B [Member]	Apr. 30, 2010 Tax Exempt Revenue Refunding Bonds Series 1997B [Member]	Apr. 30, 2011 Tax Exempt Revenue Refunding Bonds Series 1997C [Member]	Apr. 30, 2010 Tax Exempt Revenue Refunding Bonds Series 1997C [Member]	Feb. 28, 2011 Senior Notes Due In February 2011 [Member]	Feb. 28, 2011 Gulf Opportunity Zone Revenue Bonds Series 2010 [Member]	May 31, 2011 Senior Notes Due In May 2011 [Member]	Jun. 30, 2010 Debenture Due In June 2010 [Member]	May 31, 2010 Senior Notes Due In May 2014 [Member]
Non-Bank Debt (Textual)
Debt repayments			$ 718	$ 517				$ 294	$ 8	$ 8							$ 210	$ 300	$ 200	$ 25	$ 190
Interest rate of notes in percentage					4.50%	6.125%		7.50%			5.45%	5.45%	5.40%	5.40%	5.40%	5.40%	6.75%		6.125%	7.25%	6.75%
Debt instrument maturity date (month, day, year)								Jun. 15, 2015													May 01, 2014
Redemption value in percentage								102.50%													102.25%
Debt instruments maturity date (month, year)					February 2015	February 2020
Notes issued, face amount					400	850
Proceeds from issuance of notes before deducting underwriting discounts and other issuance costs			0	1,244			1,244
Capitalized Interest (Textual)
Interest Costs Incurred, Capitalized	$ 33	$ 22	$ 60	$ 42