Employee Benefit Plans Employee Benefit Plans (Details Textuals 2) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended					12 Months Ended							1 Months Ended	12 Months Ended				1 Months Ended	12 Months Ended			1 Months Ended	12 Months Ended			1 Months Ended	12 Months Ended			1 Months Ended	12 Months Ended	1 Months Ended	12 Months Ended			3 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012	Mar. 06, 2014	Mar. 05, 2013	Sep. 30, 2014 Employee Stock Option [Member]	Sep. 30, 2013 Employee Stock Option [Member]	Sep. 30, 2012 Employee Stock Option [Member]	Sep. 30, 2014 Employee Stock Option [Member] Minimum [Member]	Sep. 30, 2014 Employee Stock Option [Member] Maximum [Member]	Sep. 30, 2014 Employee Stock Option [Member] March Two Thousand Fourteen Grant [Member] [Member] Minimum [Member]	Sep. 30, 2014 Employee Stock Option [Member] March Two Thousand Fourteen Grant [Member] [Member] Maximum [Member]	Sep. 30, 2010 Restricted Stock Units (RSUs) [Member] September Two Thousand Ten Grant [Member]	Sep. 30, 2012 Restricted Stock Units (RSUs) [Member] September Two Thousand Ten Grant [Member]	Sep. 30, 2014 Performance Shares [Member]	Sep. 30, 2013 Performance Shares [Member]	Sep. 30, 2012 Performance Shares [Member]	Nov. 30, 2011 Performance Shares [Member] November Two Thousand Eleven Grant [Member]	Sep. 30, 2014 Performance Shares [Member] November Two Thousand Eleven Grant [Member]	Sep. 30, 2013 Performance Shares [Member] November Two Thousand Eleven Grant [Member]	Sep. 30, 2012 Performance Shares [Member] November Two Thousand Eleven Grant [Member]	Jan. 31, 2014 Performance Shares [Member] January Two Thousand Fourteen Grant [Member]	Sep. 30, 2014 Performance Shares [Member] January Two Thousand Fourteen Grant [Member]	Sep. 30, 2014 Performance Shares [Member] January Two Thousand Fourteen Grant [Member] Minimum [Member]	Sep. 30, 2014 Performance Shares [Member] January Two Thousand Fourteen Grant [Member] Maximum [Member]	Nov. 30, 2012 Performance Shares [Member] November Two Thousand Twelve Grant [Member]	Sep. 30, 2014 Performance Shares [Member] November Two Thousand Twelve Grant [Member]	Sep. 30, 2013 Performance Shares [Member] November Two Thousand Twelve Grant [Member]	Sep. 30, 2012 Performance Shares [Member] November Two Thousand Twelve Grant [Member]	Jan. 31, 2013 Performance Shares [Member] January Two Thousand Thirteen Grant [Member]	Sep. 30, 2013 Performance Shares [Member] January Two Thousand Thirteen Grant [Member]	Nov. 30, 2013 Performance Shares [Member] November Two Thousand Thirteen Grant [Member]	Sep. 30, 2014 Performance Shares [Member] November Two Thousand Thirteen Grant [Member]	Sep. 30, 2013 Performance Shares [Member] November Two Thousand Thirteen Grant [Member]	Sep. 30, 2012 Performance Shares [Member] November Two Thousand Thirteen Grant [Member]	Dec. 31, 2014 Subsequent Event [Member] Performance Shares [Member] November Two Thousand Eleven Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period									2 years	9 years 9 months	2 years	5 years												1 year	3 years
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period						10 years						10 years
Number of shares granted to purchase	3,856,166	3,676,000	0
Shares available for grant	3,800,000
Total intrinsic value of options exercised						$ 18.0	$ 14.6	$ 26.4
Aggregate intrinsic value of options outstanding						101.4
Aggregate intrinsic value of options exercisable						47.0
Lower range of options outstanding exercise price						$ 9.03
Upper range of options outstanding exercise price						$ 36.92
Weighted average remaining contractual term of options outstanding						6 years 1 month
Weighted average remaining contractual term of options exercisable						4 years 7 months
Stock Option Grant Recipients				520	500
Weighted average fair value per share of options granted	$ 11.21	$ 10.92
Stock based compensation expense	26.2	19.0	18.1			25.5	18.6	15.1
Unrecognized compensation expense related to options						71.7
Weighted average period over which unrecognized compensation cost is expected to be recognized						3 years 9 months
Number of units granted													200,000					350,000				6,667				350,000				33,333		350,000
Performance period													2 years		3 years
Range of percentage of units vested upon achieving performance criteria, low													0.00%		0.00%
Range of percentage of units vested upon achieving performance criteria, high													200.00%		200.00%
Grant date fair value per unit													$ 11.53					$ 11.79				$ 21.58				$ 22.15				$ 21.49		$ 19.64
Number of units earned														325,000					568,750
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures																																				568,750
Liabilities for share-based compensation															19.2	10.1			11.7	7.4							4.9	2.7					2.6	0
Share-based compensation expense														$ 2.6	$ 9.1	$ 6.0	$ 4.1		$ 4.3	$ 3.3	$ 4.1		$ 0.3				$ 2.2	$ 2.7	$ 0		$ 0.2		$ 2.6	$ 0	$ 0