Loans (Not Covered by Share Agreements (Percentage)) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Recorded Investment [Line Items]
Loans delinquent 30-89 days as a percentage of total loans	0.33%	0.21%
Loans secured by real estate property in process of foreclosure	$ 2.7
Threshold period past due, nonperforming status of loans and leases	90 days
Period of repayment performance, minimum	6 months
Nonpass
Financing Receivable, Recorded Investment [Line Items]
Percent of nonaccrual loans	14.00%	16.00%
Special Mention
Financing Receivable, Recorded Investment [Line Items]
Percent of loans	60.00%	52.00%
Substandard
Financing Receivable, Recorded Investment [Line Items]
Percent of loans	40.00%	48.00%

Financing Receivable, Period of Repayment Performance

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- Definition

Financing Receivable, Recorded Investment, 30 to 89 Days Past Due, Percentage

+ References

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- Definition

Financing Receivables, Recorded Investments, Nonaccrual Status, Percentage

+ References

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- Definition

Loans And Leases Receivable, Gross, Percentage

+ References

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- Definition

Threshold Period Past Due for Nonperforming Status of Financing Receivable

+ References

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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

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- Definition

Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 35
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL49126937-111524

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