Investment Securities - Narrative (Details)	Sep. 30, 2020
Investment securities
Debt Securities, Available-for-sale [Line Items]
Average percent of amortized cost for securities in unrealized loss positions for more than 12 months	99.20%

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.

No definition available.

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