Loans Loans (Analysis of Troubled Debt Restructurings) (Details) $ in Thousands, loan in Millions	12 Months Ended
Dec. 31, 2016 USD ($) Modifications contract	Dec. 31, 2015 USD ($) Modifications loan contract	Dec. 31, 2014 USD ($) Modifications contract
Financing Receivable, Modifications [Line Items]
Financing Receivable Modifications Additional Commitment To Lend	$ 508	$ 0
Financing Receivable, Modifications, Subsequent Default, Number of Contracts \| contract	0	0	0
FHLB Advances, Collateral Pledged	$ 1,510,514	$ 1,399,201
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing, Number of Loans \| loan		0.0
Loans, Excluding Purchased Credit Impaired Loans [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	54	7	8
Pre-Modification Outstanding Recorded Investment	$ 7,679	$ 3,808	$ 2,892
Post-Modification Outstanding Recorded Investment	$ 7,677	$ 3,790	$ 2,875
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Commercial business: Secured loans [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	9	5	4
Pre-Modification Outstanding Recorded Investment	$ 2,131	$ 3,724	$ 759
Post-Modification Outstanding Recorded Investment	$ 2,131	$ 3,706	$ 759
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	3	1	2
Pre-Modification Outstanding Recorded Investment	$ 203	$ 30	$ 494
Post-Modification Outstanding Recorded Investment	$ 203	$ 30	$ 494
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	0	1
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 143
Post-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 126
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	1	0	1
Pre-Modification Outstanding Recorded Investment	$ 250	$ 0	$ 1,496
Post-Modification Outstanding Recorded Investment	$ 250	$ 0	$ 1,496
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Consumer [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	41	1	0
Pre-Modification Outstanding Recorded Investment	$ 5,095	$ 54	$ 0
Post-Modification Outstanding Recorded Investment	$ 5,093	$ 54	$ 0

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Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing, Number of Loans

+ References

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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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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=66008989&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.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953682-111524

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