Investment Securities (Narrative) (Details) - security	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Number of securities in unrealized loss position	17	100
Number of securities in unrealized loss position, more than 12 months	12	69
MBS - GSE Residential [Member]
Debt Securities, Available-for-sale [Line Items]
Number of securities in unrealized loss position	14
Number of securities in unrealized loss position, more than 12 months	12
MBS - GSE Residential [Member] \| Measurement Input, Loss Severity [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, measurement input	0.59%
Obligations Of States And Political Subdivisions [Member]
Debt Securities, Available-for-sale [Line Items]
Number of securities in unrealized loss position	3
Obligations Of States And Political Subdivisions [Member] \| Measurement Input, Loss Severity [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, measurement input	0.34%

Debt Securities, Available-For-Sale, Measurement Input, Percentage

No definition available.

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- Definition

Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27290-111563

+ Details

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- Definition

Number of investment positions in available-for-sale investments that have been in a continuous unrealized loss position for greater than or equal to a year for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

+ 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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