Significant Accounting Policies (Narrative) (Details) - Accounting Standards Update 2016-13 [Member] - USD ($) $ in Millions	Jan. 01, 2020	Mar. 31, 2020	Dec. 31, 2019
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Cumulative effect on retained earnings net of tax	$ 25.5
Accrued interest receivable on available-for-sale debt securities		$ 2.7	$ 4.1
Accrued interest receivable on loans		$ 37.4	$ 32.7

Amount of the cumulative effect on retained earnings net of related income tax effect.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22663-107794

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