Securitizations and Variable Interest Entities Additional Information (Details) (USD $)	12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2013 Salus Capital Partners LLC	Feb. 28, 2013 Salus Capital Partners LLC	Feb. 14, 2013 Salus Capital Partners LLC	Sep. 30, 2014 Variable Interest Entity, Primary Beneficiary Salus Capital Partners LLC	Sep. 30, 2013 Variable Interest Entity, Primary Beneficiary Salus Capital Partners LLC	Sep. 23, 2013 Variable Interest Entity, Primary Beneficiary Salus Capital Partners LLC	Feb. 28, 2013 Variable Interest Entity, Primary Beneficiary Salus Capital Partners LLC	Sep. 30, 2014 Unaffiliated long-term debt of consolidated variable-interest entity Variable Interest Entity, Primary Beneficiary Salus Capital Partners LLC	Sep. 30, 2013 Unaffiliated long-term debt of consolidated variable-interest entity Variable Interest Entity, Primary Beneficiary Salus Capital Partners LLC
Variable Interest Entity [Line Items]
Asset-based loans	$ 811,600,000	$ 560,400,000	$ 136,500,000	$ 166,900,000	$ 331,100,000	$ 331,100,000		$ 325,000,000	$ 175,500,000
Document Period End Date	Sep. 30, 2014
Variable Interest Entity, Consolidated, Carrying Amount, Asset-Backed Loans Receivable						455,900,000	337,800,000
Collateralized loan obligation of consolidated VIE					182,900,000	192,000,000	181,800,000
Debt Instrument, Unamortized Discount										1,000,000	1,100,000
Variable Interest Entity, Consolidated, Carrying Amount, Asset-Backed Loans Receivable, Portion Sellers Interest						$ 292,000,000	$ 302,100,000