Derivatives (Derivatives Associated with Capital Markets Trading Activities) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
Customer Interest Rate Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional	$ 1,742,060	$ 1,439,306
Assets	88,154	137,958
Liabilities	6,880	923
Offsetting Upstream Interest Rate Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional	1,742,060	1,439,306
Assets	6,880	923
Liabilities	88,154	137,958
Put Option [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional		5,000
Assets, Option Contracts		1
Liabilities, Option Contracts		0
Forwards And Futures Purchased [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional	1,664,813	4,361,583
Assets, Forwards and Futures	208	1,173
Liabilities, Forwards and Futures	9,296	10,662
Forwards And Futures Sold [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional	2,038,677	4,706,866
Assets, Forwards and Futures	16,669	13,147
Liabilities, Forwards and Futures	$ 474	$ 1,762