Loans Loans (Analysis of Troubled Debt Restructurings) (Details) loan in Millions	12 Months Ended
Dec. 31, 2019 USD ($) Modifications contract	Dec. 31, 2018 USD ($) loan Modifications contract	Dec. 31, 2017 USD ($) Modifications contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable Modifications Additional Commitment To Lend	$ 1,100,000	$ 2,100,000
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts \| contract	1	0	0
Financing Receivable, Troubled Debt Restructuring, Subsequent Default	$ 26,000	$ 0	$ 0
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, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	24	34	60
Pre-Modification Outstanding Recorded Investment	$ 7,348,000	$ 22,047,000	$ 18,122,000
Post-Modification Outstanding Recorded Investment	$ 7,348,000	$ 22,047,000	$ 18,122,000
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Commercial business: Secured loans [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	11	12	10
Pre-Modification Outstanding Recorded Investment	$ 6,642,000	$ 18,379,000	$ 5,655,000
Post-Modification Outstanding Recorded Investment	$ 6,642,000	$ 18,379,000	$ 5,655,000
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Commercial business: Unsecured loans [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	0	0	1
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 26,000
Post-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 26,000
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Real estate: One-to-four family residential [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	1	0	3
Pre-Modification Outstanding Recorded Investment	$ 45,000	$ 0	$ 583,000
Post-Modification Outstanding Recorded Investment	$ 45,000	$ 0	$ 583,000
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Real estate: Commercial and multifamily residential: Commercial land [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	0	0	1
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 687,000
Post-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 687,000
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Real estate: Commercial and multifamiIy residential: Income property [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	1	1	1
Pre-Modification Outstanding Recorded Investment	$ 217,000	$ 891,000	$ 1,152,000
Post-Modification Outstanding Recorded Investment	$ 217,000	$ 891,000	$ 1,152,000
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Real estate: Commercial and multifamiIy residential: Owner occupied [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	0	0	1
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 78,000
Post-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 78,000
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Real estate construction: Commercial and multifamily residential: Owner occupied [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	0	0	1
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 4,050,000
Post-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 4,050,000
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Consumer [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	11	21	42
Pre-Modification Outstanding Recorded Investment	$ 444,000	$ 2,777,000	$ 5,891,000
Post-Modification Outstanding Recorded Investment	$ 444,000	$ 2,777,000	$ 5,891,000

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- Definition

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

+ References

No definition available.

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+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524

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+ References

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+ References

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- Definition

Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953682-111524

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Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953682-111524

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