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Loans (Analysis of Nonaccrual Loans) (Details) - USD ($) $ in Thousands | Mar. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Financing Receivable, Recorded Investment [Line Items] |  |
Recorded Investment Nonaccrual Loans | $ 78,464 | $ 66,189
Unpaid Principal Balance Nonaccrual Loans | 91,271 | 79,886
Secured Loans [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Recorded Investment Nonaccrual Loans | 57,504 | 45,410
Unpaid Principal Balance Nonaccrual Loans | 69,056 | 56,865
Unsecured Loans [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Recorded Investment Nonaccrual Loans | 115 | 50
Unpaid Principal Balance Nonaccrual Loans | 115 | 49
One-to-Four Family Residential [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Recorded Investment Nonaccrual Loans | 1,054 | 785
Unpaid Principal Balance Nonaccrual Loans | 1,426 | 1,182
Commercial Land [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Recorded Investment Nonaccrual Loans | 3,192 | 2,628
Unpaid Principal Balance Nonaccrual Loans | 3,201 | 2,623
Income Property Multifamily [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Recorded Investment Nonaccrual Loans | 3,980 | 4,284
Unpaid Principal Balance Nonaccrual Loans | 4,264 | 5,410
Owner Occupied [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Recorded Investment Nonaccrual Loans | 7,367 | 7,029
Unpaid Principal Balance Nonaccrual Loans | 7,621 | 7,270
Land And Acquisition [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Recorded Investment Nonaccrual Loans | 0 | 25
Unpaid Principal Balance Nonaccrual Loans | 0 | 26
Residential Construction [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Recorded Investment Nonaccrual Loans | 1,210 | 1,829
Unpaid Principal Balance Nonaccrual Loans | 1,210 | 1,828
Consumer Portfolio Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Recorded Investment Nonaccrual Loans | 4,042 | 4,149
Unpaid Principal Balance Nonaccrual Loans | $ 4,378 | $ 4,633

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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 + Details
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