Fair Value Measurements - Valuation Techniques, Significant Unobservable Inputs, Quantitative Information Non-recurring Basis (Detail) - Fair Value, Measurements, Nonrecurring - LEVEL 3 $ in Millions	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Discount to reflect realizable value \| Lower Limit
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans, Range of Discounts Applied	0.150	0.150
OREO, Range of Discounts Applied	0.150	0.150
Discount to reflect realizable value \| Upper Limit
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans, Range of Discounts Applied	0.300	0.250
OREO, Range of Discounts Applied	0.300	0.200
Loans \| Discount to reflect realizable value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
FAIR VALUE	$ 24.9	$ 12.2
OREO
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
FAIR VALUE	$ 0.4	$ 0.3

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

+ Details

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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

No definition available.

+ Details

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- Definition

Value of input used to measure real estate owned by financial institution by financial institution which is not directly related to its business.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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