Loans (Narrative) (Details) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019 USD ($) contract	Sep. 30, 2018 contract	Sep. 30, 2019 USD ($) contract	Sep. 30, 2018 contract	Dec. 31, 2018 USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts \| contract	0	0	1	0
Loans Receivable [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged	$ 3,180.0		$ 3,180.0		$ 3,220.0
Federal Reserve Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged	$ 138.9		$ 138.9		$ 82.0

Federal Reserve Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged

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- Definition

Amount of the collateral pledged in support of federal home loan bank advances outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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- Definition

Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953682-111524

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+ References

No definition available.

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