Borrowings and Related Interest(Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Debt Instrument [Line Items]
Other borrowings	$ 394		$ 153
Subordinated Debt	36,083		36,083
Gains Losses On Extinguishment Of Debt	0	$ 0
Federal Home Loan Bank Advances [Member]
Debt Instrument [Line Items]
Loans pledged as collateral to secure FHLB advances	972,800		1,300,000
Additional Borrowing Capacity	$ 925,200		$ 920,000
Weighted average period remaining maturity of FHLB advances	5.8 months		3.2 months
Interest Payable	$ 75
Minimum amount of qualifying collateral	110.00%
Repurchase agreement
Debt Instrument [Line Items]
Interest Payable	$ 426		$ 369

Weighted average maturity (weighted by amount of the agreement) of FHLB advances.

No definition available.

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- Definition

Minimum amount of qualifying collateral of the fair value of outstanding advances.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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- Definition

Amount of interest payable on debt, including, but not limited to, trade payables.

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- Definition

Amount before allowance of mortgage loans on existing land or building. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans covered under loss sharing agreements.

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- Definition

The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

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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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