Loans - Loans in Process of Foreclosure (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance	$ 33,181	$ 46,842
Total Recorded Investment	26,250	31,548
Residential Mortgage Loans [Member] \| Loans In Process Of Foreclosure [Member]
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance	2,588	3,025
Total Recorded Investment	2,428	2,576
Consumer Loans [Member] \| Loans In Process Of Foreclosure [Member]
Financing Receivable Impaired [Line Items]
Unpaid Principal Balance	613	1,069
Total Recorded Investment	$ 608	$ 795

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

The balance of financing receivables that were individually evaluated for impairment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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