Debt and Financing Arrangements (Details Textuals 1)	3 Months Ended						12 Months Ended																											12 Months Ended		3 Months Ended					3 Months Ended											3 Months Ended						3 Months Ended		3 Months Ended
	Jun. 30, 2011 EquityUnit	Mar. 31, 2011 USD ($)	Dec. 31, 2010 USD ($)	Jun. 30, 2010 USD ($) Note	Dec. 31, 2009 USD ($) Note	Sep. 30, 2009	Sep. 30, 2011 USD ($)	Sep. 30, 2010 USD ($)	Sep. 30, 2009 USD ($)	Sep. 30, 2010 5.25% due in 2011 [Member] USD ($)	Sep. 30, 2011 5.8% due in 2013 [Member] USD ($)	Sep. 30, 2010 5.8% due in 2013 [Member] USD ($)	Sep. 30, 2011 4.875% due in 2013 [Member] USD ($)	Sep. 30, 2010 4.875% due in 2013 [Member] USD ($)	Sep. 30, 2011 Floating rate senior unsecured notes due 2014 [Member] USD ($)	Mar. 31, 2011 Floating rate senior unsecured notes due 2014 [Member] USD ($)	Sep. 30, 2011 1.75% unsecured fixed rate notes due 2014 [Member] USD ($)	Mar. 31, 2011 1.75% unsecured fixed rate notes due 2014 [Member] USD ($)	Sep. 30, 2011 7.7% due in 2015 [Member] USD ($)	Sep. 30, 2010 7.7% due in 2015 [Member] USD ($)	Sep. 30, 2011 5.5% due in 2016 [Member] USD ($)	Sep. 30, 2010 5.5% due in 2016 [Member] USD ($)	Sep. 30, 2011 7.125% due in 2017 [Member] USD ($)	Sep. 30, 2010 7.125% due in 2017 [Member] USD ($)	Sep. 30, 2011 5.0% senior unsecured fixed rate notes due 2020 [Member] USD ($)	Sep. 30, 2010 5.0% senior unsecured fixed rate notes due 2020 [Member] USD ($)	Mar. 31, 2010 5.0% senior unsecured fixed rate notes due 2020 [Member] USD ($)	Sep. 30, 2011 4.25% senior unsecured fixed rate notes due 2021 [Member] USD ($)	Mar. 31, 2011 4.25% senior unsecured fixed rate notes due 2021 [Member] USD ($)	Sep. 30, 2011 6.0% due in 2036 [Member] USD ($)	Sep. 30, 2010 6.0% due in 2036 [Member] USD ($)	Sep. 30, 2011 5.7% senior unsecured fixed rate notes due 2041 [Member] USD ($)	Mar. 31, 2011 5.7% senior unsecured fixed rate notes due 2041 [Member] USD ($)	Sep. 30, 2011 11.5% due in 2042 [Member] EquityUnit	Sep. 30, 2010 11.5% due in 2042 [Member] EquityUnit	Sep. 30, 2009 11.5% notes due in 2042 [Member] USD ($)	Sep. 30, 2011 11.5% notes due in 2042 [Member] USD ($)	Jun. 30, 2011 11.5% notes due in 2042 [Member] USD ($)	Sep. 30, 2011 6.95% due in 2046 [Member] USD ($)	Sep. 30, 2010 6.95% due in 2046 [Member] USD ($)	Mar. 31, 2011 Floating rate loan [Member] EUR (€)	Sep. 30, 2009 6.5% convertible senior notes due 2012 [Member] USD ($)	Mar. 31, 2011 5.25% fixed rate notes [Member] USD ($)	Jun. 30, 2010 5.25% fixed rate notes [Member] USD ($)	Mar. 31, 2010 5.25% fixed rate notes [Member] USD ($)	Dec. 31, 2009 5.25% fixed rate notes [Member] USD ($)	Mar. 31, 2010 3 year, floating rate loan agreement 3 [Member] JPY (¥)	Dec. 31, 2009 3 year, floating rate loan agreement 2 [Member] JPY (¥)	Dec. 31, 2009 3 year, floating rate loan agreement 1 [Member] JPY (¥)	Sep. 30, 2011 Euro [Member] EUR (€) CreditFacility	Sep. 30, 2010 Euro [Member]	Sep. 30, 2011 Euro-denominated revolving credit facility expiring in July 2012 EUR (€)	Sep. 30, 2011 Euro-denominated revolving credit facility expiring in September 2012 EUR (€) CreditFacility	Sep. 30, 2011 Euro-denominated revolving credit facility expiring in August 2014 [Member] EUR (€)	Jun. 30, 2011 150 million euro revolving credit facility [Member] EUR (€)	Jun. 30, 2011 50 million euro revolving credit facility [Member] EUR (€)	Jun. 30, 2010 50 million euro revolving credit facility [Member] EUR (€)	Sep. 30, 2011 Revolving credit facility expiring in September 2012 USD ($)	Sep. 30, 2010 Committed revolving facility [Member] USD ($)	Jun. 30, 2010 One year committed, revolving credit facility [Member] EUR (€)
Debt and Financing Arrangements (Textuals)
Interest rate on notes										5.25%	5.80%	5.80%	4.875%	4.875%			1.75%	1.75%	7.70%	7.70%	5.50%	5.50%	7.125%	7.125%	5.00%	5.00%	5.00%	4.25%	4.25%	6.00%	6.00%	5.70%	5.70%	11.50%	11.50%	11.50%	11.50%	11.50%	6.95%	6.95%			5.25%
Interest rate on convertible senior notes				6.50%	6.50%		6.50%																																			6.50%
Base principal amount per note																																				$ 1,000						$ 1,000
Aggregate principal amount of debt										654,000,000	100,000,000	100,000,000	300,000,000	300,000,000	350,000,000	350,000,000	450,000,000	450,000,000	125,000,000	125,000,000	800,000,000	800,000,000	150,000,000	150,000,000	500,000,000	500,000,000	500,000,000	500,000,000	500,000,000	400,000,000	400,000,000	300,000,000	300,000,000				8,000,000	8,000,000	125,000,000	125,000,000	100,000,000
Debt retired, amount			82,000,000																																								654,000,000	18,000,000	61,000,000	13,000,000	18,000,000,000	7,000,000,000	12,000,000,000
Length of debt, years																																									6 years						3 years	3 years	3 years
Number of equity units outstanding at end of period																																		760,100	917,915
Cash payment per base principal amount of convertible senior notes																																										120
Cash consideration per corporate unit																																				6.50
Aggregate principal amount of notes exchanged																																										400,000,000
Aggregate principal amount of Equity Units in form of Corporate Units exchanged																																				404,000,000
Common stock shares exchanged as part of announced exchange offer																																				39,000,000						36,000,000
Cash exchanged as part of announced exchange offer																																				65,000,000						61,000,000
Conversion rate of notes to shares of common stock																																										89.3855
Stock consideration per Corporate Unit																																				4.8579
Debt conversion payments																																				52,000,000						48,000,000
Accrued interest payments on notes																																				13,000,000						13,000,000
Debt conversion costs									111,000,000																											54,000,000						57,000,000
Debt conversion costs on exchange																																				53,000,000						48,000,000
Write-off of unamortized debt issuance cost																																				1,000,000						9,000,000
Undivided beneficial ownership interest in subordinated notes within equity units																																				5.00%
Common stock issued	766,673
Debt and Financing Arrangements (Textuals)
Amount of credit facility																																																		223,000,000		50,000,000	36,500,000	100,000,000				50,000,000	100,000,000	50,000,000
Number of euro denominated revolving credit facilities																																																		4			2
Facility expiry date																																																				July 2012	September 2012	August 2014				September 2012
Length of credit facility, years																																																												1 year
Amount of credit facility retired																																																							150,000,000	50,000,000	50,000,000
Weighted-average interest rate of debt																																																		4.70%	5.00%
Installments of long-term debt maturing 2012							17,000,000
Installments of long-term debt maturing 2013							437,000,000
Installments of long-term debt maturing 2014							930,000,000
Installments of long-term debt maturing 2015							132,000,000
Installments of long-term debt maturing 2016							805,000,000
Installments of long-term debt maturing 2017 and thereafter							2,229,000,000
Interest paid on short and long-term debt							216,000,000	181,000,000	358,000,000
Number of equity units exercised	157,820
Aggregate net proceeds from the issues of notes		1,600,000,000
Number of convertible senior notes redeemed				200
Par value of convertible senior notes redeemed				200,000
Number of convertible senior notes repurchased					1,685
Par value of convertible senior notes repurchased					$ 1,685,000
Number of outstanding equity units in form of corporate units offered for exchange						8,550,000
Number of outstanding equity units in form of corporate units exchanged						8,082,085