Loans Loans (Analysis of Troubled Debt Restructurings) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014 contract	Dec. 31, 2013 contract	Dec. 31, 2012 contract
Financing Receivable, Modifications [Line Items]
Financing Receivable Modifications Additional Commitment To Lend	$ 0	$ 0
Financing Receivable, Modifications, Subsequent Default, Number of Contracts	0	0	0
FHLB Advances, Collateral Pledged	1,083,879	1,075,389
Loans, Excluding Purchased Credit Impaired Loans [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	8	12	2
Pre-Modification Outstanding Recorded Investment	2,892	1,968	4,474
Post-Modification Outstanding Recorded Investment	2,875	1,968	2,844
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Secured Loans [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	4	2	1
Pre-Modification Outstanding Recorded Investment	759	190	195
Post-Modification Outstanding Recorded Investment	759	190	194
Loans, Excluding Purchased Credit Impaired Loans [Member] \| One-to-Four Family Residential [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	2	1	0
Pre-Modification Outstanding Recorded Investment	494	113	0
Post-Modification Outstanding Recorded Investment	494	113	0
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Commercial Land [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	0	1	0
Pre-Modification Outstanding Recorded Investment	0	137	0
Post-Modification Outstanding Recorded Investment	0	137	0
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Income Property Multifamily [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	1	4	1
Pre-Modification Outstanding Recorded Investment	143	1,186	4,279
Post-Modification Outstanding Recorded Investment	126	1,186	2,650
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Owner Occupied [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	1	1	0
Pre-Modification Outstanding Recorded Investment	1,496	172	0
Post-Modification Outstanding Recorded Investment	1,496	172	0
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Land And Acquisition [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	0	1	0
Pre-Modification Outstanding Recorded Investment	0	117	0
Post-Modification Outstanding Recorded Investment	0	117	0
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Consumer Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	0	2	0
Pre-Modification Outstanding Recorded Investment	0	53	0
Post-Modification Outstanding Recorded Investment	$ 0	$ 53	0

Financing Receivable Modifications Additional Commitment To Lend

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- Definition

Amount of the collateral pledged in support of federal home loan bank advances outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 50

-Paragraph 3

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 33

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953676-111524

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Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

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Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 34

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953682-111524

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