Mortgage Banking (Details Textual) (USD $) In Billions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Residential Mortgage Loans Unpaid Balance	$ 1.3	$ 1.3

Total carrying amount of residential mortgage loans unpaid as of the balance sheet date.

No definition available.

Name:	fdef_ResidentialMortgageLoansUnpaidBalance
Namespace Prefix:	fdef_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant