Troubled Debt Restructurings (Loans By Class of Financing Receivable Modified as TDRs) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($) contract	Dec. 31, 2017 USD ($) contract	Dec. 31, 2016 USD ($) contract
Troubled Debt Restructuring, Subsequent Periods [Line Items]
Number of Contracts	19	21
Troubled Debt Restructurings Within Previous Twelve Months [Member]
Troubled Debt Restructuring, Subsequent Periods [Line Items]
Number of Contracts	0	0	2
Financing Receivable, Modifications, Subsequent Default, Recorded Investment \| $	$ 0	$ 0	$ 588
Residential Single Family [Member] \| Troubled Debt Restructurings Within Previous Twelve Months [Member]
Troubled Debt Restructuring, Subsequent Periods [Line Items]
Number of Contracts			2
Financing Receivable, Modifications, Subsequent Default, Recorded Investment \| $			$ 588

Troubled Debt Restructuring, Subsequent Periods [Line Items]

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- Definition

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=84173941&loc=SL6953676-111524

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- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524

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