Loans (Analysis of Nonaccrual Loans) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	$ 66,189
Unpaid Principal Balance Nonaccrual Loans	79,886	$ 42,289
Recorded Investment Nonaccrual Loans		27,756
Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	4,149
Unpaid Principal Balance Nonaccrual Loans	4,633	4,331
Recorded Investment Nonaccrual Loans		3,883
Commercial business: Secured loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	45,410
Unpaid Principal Balance Nonaccrual Loans	56,865	21,503
Recorded Investment Nonaccrual Loans		11,524
Commercial business: Unsecured loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	50
Unpaid Principal Balance Nonaccrual Loans	49	303
Recorded Investment Nonaccrual Loans		31
Real estate: One-to-four family residential [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	785
Unpaid Principal Balance Nonaccrual Loans	1,182	1,302
Recorded Investment Nonaccrual Loans		568
Real estate: Commercial and multifamily residential: Commercial land [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	2,628
Unpaid Principal Balance Nonaccrual Loans	2,623	922
Recorded Investment Nonaccrual Loans		934
Real estate: Commercial and multifamiIy residential: Income property [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	4,284
Unpaid Principal Balance Nonaccrual Loans	5,410	4,247
Recorded Investment Nonaccrual Loans		4,005
Real estate: Commercial and multifamiIy residential: Owner occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	7,029
Unpaid Principal Balance Nonaccrual Loans	7,270	9,030
Recorded Investment Nonaccrual Loans		6,248
Real estate construction: One-to-four family residential: Land and acquisition [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	25
Unpaid Principal Balance Nonaccrual Loans	26	102
Recorded Investment Nonaccrual Loans		14
Real estate construction: One-to-four family residential: Residential construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	1,829
Unpaid Principal Balance Nonaccrual Loans	$ 1,828	549
Recorded Investment Nonaccrual Loans		$ 549

Financing Receivable, Recorded Investment, Gross, Nonaccrual Status

No definition available.

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- Definition

Financing Receivable Unpaid Principal Balance Nonaccrual Status.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524

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