Notes Payable (Details 2) (USD $) In Millions	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
Senior Note Retirements
Maturities of senior notes	$ 176.2	$ 194.1
Early redemption of senior notes	112.3	95.0
Repurchases of senior notes	206.9	727.2
Total retirements of senior notes	495.4	1,016.3
4.875% senior notes, matured January 2010 [Member]
Senior Note Retirements
Maturities of senior notes		130.9
9.75% senior notes, matured September 2010 [Member]
Senior Note Retirements
Maturities of senior notes		51.9
9.75% senior subordinated notes, matured September 2010 [Member]
Senior Note Retirements
Maturities of senior notes		11.3
6% senior notes matured April 2011 [Member]
Senior Note Retirements
Maturities of senior notes	70.1
7.875% senior notes, matured August 2011 [Member]
Senior Note Retirements
Maturities of senior notes	106.1
5.875% senior notes due 2013, redeemed February 2010 [Member]
Senior Note Retirements
Early redemption of senior notes		95.0
5.375% senior notes due 2012 redeemed in April 2011[Member]
Senior Note Retirements
Early redemption of senior notes	112.3
9.75% senior notes due 2010 [Member]
Senior Note Retirements
Repurchases of senior notes		18.6
9.75% senior subordinated notes due 2010
Senior Note Retirements
Repurchases of senior notes		4.0
6% senior notes due 2011, net [Member]
Senior Note Retirements
Repurchases of senior notes		142.9
7.875% senior notes due 2011, net [Member]
Senior Note Retirements
Repurchases of senior notes	12.8	44.7
5.375% senior notes due 2012 [Member]
Senior Note Retirements
Repurchases of senior notes	34.3	95.5
6.875% senior notes due 2013 [Member]
Senior Note Retirements
Repurchases of senior notes	2.6	25.2
5.875% senior notes due 2013 [Member]
Senior Note Retirements
Repurchases of senior notes		1.0
6.125% senior notes due 2014, net [Member]
Senior Note Retirements
Repurchases of senior notes	1.0	53.1
5.625% senior notes due 2014, net [Member]
Senior Note Retirements
Repurchases of senior notes	9.8	102.3
5.25% senior notes due 2015, net [Member]
Senior Note Retirements
Repurchases of senior notes	42.7	99.5
5.625% senior notes due 2016, net [Member]
Senior Note Retirements
Repurchases of senior notes	56.5	73.4
6.5% senior notes due 2016, net [Member]
Senior Note Retirements
Repurchases of senior notes	$ 47.2	$ 67.0