Loans Loans (Analysis of Troubled Debt Restructurings) (Details) loan in Millions	12 Months Ended
Dec. 31, 2018 USD ($) Modifications contract	Dec. 31, 2017 USD ($) loan Modifications contract	Dec. 31, 2016 USD ($) Modifications contract
Financing Receivable, Modifications [Line Items]
Financing Receivable Modifications Additional Commitment To Lend	$ 2,100,000	$ 506,000
Financing Receivable, Modifications, Subsequent Default, Number of Contracts \| contract	0	0	0
Financing Receivable, Modifications, Subsequent Default, Recorded Investment	$ 0	$ 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, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	34	60	54
Pre-Modification Outstanding Recorded Investment	$ 22,047,000	$ 18,122,000	$ 7,679,000
Post-Modification Outstanding Recorded Investment	$ 22,047,000	$ 18,122,000	$ 7,677,000
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Commercial business: Secured loans [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	12	10	9
Pre-Modification Outstanding Recorded Investment	$ 18,379,000	$ 5,655,000	$ 2,131,000
Post-Modification Outstanding Recorded Investment	$ 18,379,000	$ 5,655,000	$ 2,131,000
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Commercial business: Unsecured loans [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	0	1	0
Pre-Modification Outstanding Recorded Investment	$ 0	$ 26,000	$ 0
Post-Modification Outstanding Recorded Investment	$ 0	$ 26,000	$ 0
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	0	3	3
Pre-Modification Outstanding Recorded Investment	$ 0	$ 583,000	$ 203,000
Post-Modification Outstanding Recorded Investment	$ 0	$ 583,000	$ 203,000
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	1	0
Pre-Modification Outstanding Recorded Investment	$ 0	$ 687,000	$ 0
Post-Modification Outstanding Recorded Investment	$ 0	$ 687,000	$ 0
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	1	1	0
Pre-Modification Outstanding Recorded Investment	$ 891,000	$ 1,152,000	$ 0
Post-Modification Outstanding Recorded Investment	$ 891,000	$ 1,152,000	$ 0
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	$ 78,000	$ 250,000
Post-Modification Outstanding Recorded Investment	$ 0	$ 78,000	$ 250,000
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Real estate construction: Commercial and multifamily residential: Owner occupied [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	0	1	0
Pre-Modification Outstanding Recorded Investment	$ 0	$ 4,050,000	$ 0
Post-Modification Outstanding Recorded Investment	$ 0	$ 4,050,000	$ 0
Loans, Excluding Purchased Credit Impaired Loans [Member] \| Consumer [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	21	42	41
Pre-Modification Outstanding Recorded Investment	$ 2,777,000	$ 5,891,000	$ 5,095,000
Post-Modification Outstanding Recorded Investment	$ 2,777,000	$ 5,891,000	$ 5,093,000

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

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
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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
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-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
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