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Long-Term Debt.

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The price per share of the conversion feature embedded in the debt instrument.

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Description of the conversion terms of a debt instrument which may include the conversion ratio (including all potential conversion ratios if contingently adjustable), type of debt or equity security into which the debt is convertible, the dollars of debt or the number of shares into which the instrument is convertible (or potentially convertible into), the conversion period, any contingencies associated with the conversion terms, and the existence and amount of a beneficial conversion feature.

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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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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Interest rate stated in the contractual debt agreement.

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Amount borrowed under the credit facility as of the balance sheet date.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The cash inflow from a borrowing with the highest claim on the assets of the entity in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle, if longer).

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Long-Term Debt (Details) (USD $)	3 Months Ended	8 Months Ended	9 Months Ended					3 Months Ended					3 Months Ended					1 Months Ended						1 Months Ended								9 Months Ended
Long-Term Debt (Details) (USD $)	Sep. 30, 2007	Aug. 31, 2010	Aug. 31, 2011	Nov. 30, 2011	Aug. 26, 2011	Feb. 25, 2011	Nov. 30, 2010	Sep. 30, 2007 7.75% Senior Notes, due 2012 [Member]	Aug. 31, 2011 7.75% Senior Notes, due 2012 [Member]	Nov. 30, 2010 7.75% Senior Notes, due 2012 [Member]	Aug. 31, 2011 5.875% Senior Notes, due 2014 [Member]	Nov. 30, 2010 5.875% Senior Notes, due 2014 [Member]	Nov. 30, 2010 3.875% Senior Note, due 2015 [Member]	Aug. 31, 2011 3.875% Senior Note, due 2015 [Member]	Nov. 02, 2010 3.875% Senior Note, due 2015 [Member]	Aug. 31, 2011 5.5% Senior Notes, due 2016 [Member]	Nov. 30, 2010 5.5% Senior Notes, due 2016 [Member]	Apr. 30, 2011 5.125% Senior Notes, due 2018 [Member]	Aug. 31, 2011 5.125% Senior Notes, due 2018 [Member]	Apr. 08, 2011 5.125% Senior Notes, due 2018 [Member]	Nov. 30, 2010 5.125% Senior Notes, due 2018 [Member]	Aug. 31, 2011 8.5% Senior Notes, due 2019 [Member]	Nov. 30, 2010 8.5% Senior Notes, due 2019 [Member]	Jul. 31, 2010 6.875% Senior Note, due 2021 [Member]	Jun. 30, 2010 6.875% Senior Note, due 2021 [Member]	Aug. 31, 2011 6.875% Senior Note, due 2021 [Member]	Nov. 30, 2010 6.875% Senior Note, due 2021 [Member]	Jul. 15, 2010 6.875% Senior Note, due 2021 [Member]	Jun. 24, 2010 6.875% Senior Note, due 2021 [Member]	Aug. 31, 2011 6.45% Senior Debentures, due 2027 [Member]	Nov. 30, 2010 6.45% Senior Debentures, due 2027 [Member]	Aug. 31, 2011 3.875% Convertible Senior Debentures, due, 2029 [Member]	Nov. 30, 2010 3.875% Convertible Senior Debentures, due, 2029 [Member]	Aug. 31, 2011 6.25% Senior Debentures, due 2036 [Member]	Nov. 30, 2010 6.25% Senior Debentures, due 2036 [Member]
Summary of long-term debt carrying values including unamortized discounts and premiums
Long-term debt			$ 4,580,978,000				$ 3,778,681,000		$ 305,232,000	$ 305,969,000	$ 249,234,000	$ 249,048,000	$ 499,000,000	$ 499,140,000		$ 348,997,000	$ 348,854,000		$ 797,342,000		$ 0	$ 707,977,000	$ 708,529,000			$ 545,737,000	$ 545,510,000			$ 346,633,000	$ 346,544,000	$ 287,944,000	$ 282,577,000	$ 492,742,000	$ 492,650,000
Interest rates									7.75%		5.875%			3.875%		5.50%			5.125%			8.50%				6.875%				6.45%		3.875%		6.25%
Effective interest rates									8.08%		6.00%			3.92%		5.57%			5.18%			8.31%				6.99%				6.55%		7.20%		6.37%
Par value of notes issued								200,000,000							500,000,000					800,000,000								150,000,000	400,000,000			345,000,000
Proceeds from notes issued		543,510,000	794,587,000										497,700,000					794,600,000						148,700,000	394,200,000
3.875% convertible senior debenture Principal amount																																1,000
Conversion price of common stock																																$ 38.35
Debt Instrument Convertible Conversion Ratio																																26.0754
Portion of interest expense amortized								1,900,000
Long-Term Debt (Textuals) [Abstract]
Debentures convertible at holder's options			1) Companies common stock price is greater than 130% of the conversion price for at least 20 trading days in a period of 30 consecutive trading days; 2) if the trading price per debenture is less than 95% of the price of companies common stock times the conversion ratio for any 10 consecutive trading days; 3) if the debentures are called for redemption; or 4) upon the occurrence of specific corporate actions.
Description of Contingent Debenture Interest Payment			beginning on November 1, 2017, contingent interest will accrue at 0.375% if the average trading price of a debenture for 5 trading days ending on and including the third trading day immediately preceding a six-month interest period equals or exceed $1,200 per $1,000 debenture
Cash proceeds on termination of interest rate swap agreement	8,500,000
Description to Redeem the debentures for par, plus accrued interest			on or after November 1, 2012 if the price of our common stock is greater than 130% of the conversion price for at least 20 days in a period of 30 consecutive trading days and we may redeem the debentures for par, plus accrued interest, at our election any time on or after November 1, 2017
Secured revolving credit facility			950,000,000		950,000,000	1,000,000,000
Borrowed unsecured credit facility			250,000,000
Borrowings outstanding under the Credit Facility			$ 0	$ 0			$ 0