Loans Loans (Analysis of Troubled Debt Restructurings) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2015 USD ($) contract Modifications	Dec. 31, 2014 USD ($) contract Modifications	Dec. 31, 2013 USD ($) contract Modifications
Financing Receivable, Modifications [Line Items]
Financing Receivable Modifications Additional Commitment To Lend	$ 0	$ 0	$ 0
Financing Receivable, Modifications, Subsequent Default, Number of Contracts \| contract	0	0	0
FHLB Advances, Collateral Pledged	$ 1,399,201	$ 1,083,879
Loans, Excluding Purchased Credit Impaired Loans [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	7	8	12
Pre-Modification Outstanding Recorded Investment	$ 3,808	$ 2,892	$ 1,968
Post-Modification Outstanding Recorded Investment	$ 3,790	$ 2,875	$ 1,968
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Commercial business: Secured loans [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	5	4	2
Pre-Modification Outstanding Recorded Investment	$ 3,724	$ 759	$ 190
Post-Modification Outstanding Recorded Investment	$ 3,706	$ 759	$ 190
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Real estate: One-to-four family residential [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	1	2	1
Pre-Modification Outstanding Recorded Investment	$ 30	$ 494	$ 113
Post-Modification Outstanding Recorded Investment	$ 30	$ 494	$ 113
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Real estate: Commercial and multifamily residential: Commercial land [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	0	0	1
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 137
Post-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 137
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Real estate: Commercial and multifamiIy residential: Income property [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	0	1	4
Pre-Modification Outstanding Recorded Investment	$ 0	$ 143	$ 1,186
Post-Modification Outstanding Recorded Investment	$ 0	$ 126	$ 1,186
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Real estate: Commercial and multifamiIy residential: Owner occupied [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	0	1	1
Pre-Modification Outstanding Recorded Investment	$ 0	$ 1,496	$ 172
Post-Modification Outstanding Recorded Investment	$ 0	$ 1,496	$ 172
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Real estate construction: One-to-four family residential: Land and acquisition [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	0	0	1
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 117
Post-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 117
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Consumer [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	1	0	2
Pre-Modification Outstanding Recorded Investment	$ 54	$ 0	$ 53
Post-Modification Outstanding Recorded Investment	$ 54	$ 0	$ 53

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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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-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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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=49124121&loc=SL6953676-111524

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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=49124121&loc=SL6953682-111524

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