Financial Instruments with Off-Balance Sheet Risk (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012
Entity Information [Line Items]
Credit Extension Commitments	$ 1,120,190
Credit Extension Commitments, Beyond One Year	290,844
Standby Letters of Credit
Entity Information [Line Items]
Credit Extension Commitments	68,895
Unused Credit Card Lines
Entity Information [Line Items]
Credit Extension Commitments	$ 301,647