Fair Value (Details 5) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Financial Assets, Carrying Value:
Cash and cash equivalents, Carrying Value	$ 112,936	$ 179,318	$ 136,832	$ 174,931
Investment securities, Carrying Value	239,634us-gaap_MarketableSecurities	198,557us-gaap_MarketableSecurities
Federal Home Loan Bank stock, Carrying Value	13,802us-gaap_FederalHomeLoanBankStock	19,350us-gaap_FederalHomeLoanBankStock
Loans, net, including loans held for sale, Carrying Value	1,626,555fdef_LoansAndLoansReceivableHeldforsale	1,564,618fdef_LoansAndLoansReceivableHeldforsale
Accrued interest receivable, Carrying Value	6,037us-gaap_InterestReceivable	5,778us-gaap_InterestReceivable
Financial Liabilities, Carrying Value:
Deposits, Carrying Value	1,760,813us-gaap_DepositsSavingsDeposits	1,735,792us-gaap_DepositsSavingsDeposits
Advances from Federal Home Loan Bank, Carrying Value	21,544	22,520
Securities sold under repurchase agreements, Carrying Value	54,759	51,919
Subordinated debentures, Carrying Value	36,083us-gaap_SubordinatedDebt	36,083us-gaap_SubordinatedDebt
Financial Assets, Fair Value:
Cash and cash equivalents, Fair Value	112,936	179,318
Investment securities, Fair Value	239,629fdef_MarketableSecuritiesAtFairValue	198,563fdef_MarketableSecuritiesAtFairValue
Loans, net, including loans held for sale, Fair Value	1,632,507	1,568,929
Accrued interest receivable, Fair Value	6,037	5,778
Financial Liabilities, Fair Value:
Deposits, Fair Value	1,762,733us-gaap_DepositsFairValueDisclosure	1,738,216us-gaap_DepositsFairValueDisclosure
Advances from Federal Home Loan Bank, Fair Value	21,772	22,713
Securities sold under repurchase agreements, Fair Value	54,759	51,919
Subordinated debentures, Fair Value	35,307	35,237
Fair Value, Inputs, Level 1 [Member]
Financial Assets, Fair Value:
Cash and cash equivalents, Fair Value	112,936	179,318
Investment securities, Fair Value	1,990	2,372
Loans, net, including loans held for sale, Fair Value	0	0
Accrued interest receivable, Fair Value	3	4
Financial Liabilities, Fair Value:
Deposits, Fair Value	379,552	348,943
Advances from Federal Home Loan Bank, Fair Value	0	0
Securities sold under repurchase agreements, Fair Value	0	0
Subordinated debentures, Fair Value	0	0
Fair Value, Inputs, Level 2 [Member]
Financial Assets, Fair Value:
Cash and cash equivalents, Fair Value	0	0
Investment securities, Fair Value	237,639	195,609
Loans, net, including loans held for sale, Fair Value	4,741	9,140
Accrued interest receivable, Fair Value	846	696
Financial Liabilities, Fair Value:
Deposits, Fair Value	1,383,181	1,389,273
Advances from Federal Home Loan Bank, Fair Value	21,772	22,713
Securities sold under repurchase agreements, Fair Value	54,759	51,919
Subordinated debentures, Fair Value	0	0
Fair Value, Inputs, Level 3 [Member]
Financial Assets, Fair Value:
Cash and cash equivalents, Fair Value	0	0
Investment securities, Fair Value	0	582
Loans, net, including loans held for sale, Fair Value	1,627,766	1,559,789
Accrued interest receivable, Fair Value	5,188	5,078
Financial Liabilities, Fair Value:
Deposits, Fair Value	0	0
Advances from Federal Home Loan Bank, Fair Value	0	0
Securities sold under repurchase agreements, Fair Value	0	0
Subordinated debentures, Fair Value	$ 35,307	$ 35,237

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Carrying amount of interest receivable fair value disclosure of the balance date.

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Carrying amount of marketable securities at fair value of the balance date.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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Amount of interest bearing deposits with no stated maturity, which may include passbook and statement savings accounts and money-market deposit accounts (MMDAs).

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Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

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Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Fair value portion of investments in Federal Home Loan Bank (FHLBank) stock.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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Total debt and equity financial instruments including: (1) securities held-to-maturity, (2) trading securities, and (3) securities available-for-sale.

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Fair value portion of securities that an entity sells and agrees to repurchase at a specified date for a specified price.

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Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of subordinated debt (with initial maturities beyond one year or beyond the operating cycle if longer). Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

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