Loans - Summary of Recorded Investment by Category for Portfolio Loans Restructured and Subsequently Defaulted (Details) - Non-Covered Loans - Commercial and industrial	3 Months Ended	9 Months Ended
Sep. 30, 2019 USD ($) loan	Sep. 30, 2019 USD ($) loan
Schedule of Financing Receivables, Troubled Debt Restructurings - Suibsequent Defaults [Line Items]
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts \| loan	1	2
Financing Receivable, Modifications, Pre-Modification Recorded Investment \| $	$ 100,000	$ 400,000

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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- 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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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953682-111524

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