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.

+ Details

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524

+ Details

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- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

+ Details

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Period Type:	duration

- Details

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- Details

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Loans - Loans by Class Modified as TDRs with Payment Default (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($) Loan	Dec. 31, 2015 USD ($) Loan
Financing Receivable Modifications [Line Items]
Number of loans \| Loan		2	4
Recorded Investment \| $	$ 0	$ 3,606	$ 77
Commercial Loans [Member]
Financing Receivable Modifications [Line Items]
Number of loans \| Loan		1
Recorded Investment \| $		$ 3,603
Commercial Loans [Member] \| Nonresidential [Member]
Financing Receivable Modifications [Line Items]
Number of loans \| Loan		1
Recorded Investment \| $		$ 3,603
Residential Mortgage Loans [Member]
Financing Receivable Modifications [Line Items]
Number of loans \| Loan		1	2
Recorded Investment \| $		$ 3	$ 29
Residential Mortgage Loans [Member] \| One-to Four-Family [Member]
Financing Receivable Modifications [Line Items]
Number of loans \| Loan		1	2
Recorded Investment \| $		$ 3	$ 29
Consumer Loans [Member]
Financing Receivable Modifications [Line Items]
Number of loans \| Loan			2
Recorded Investment \| $			$ 48
Consumer Loans [Member] \| Home Equity [Member]
Financing Receivable Modifications [Line Items]
Number of loans \| Loan			1
Recorded Investment \| $			$ 40
Consumer Loans [Member] \| Other [Member]
Financing Receivable Modifications [Line Items]
Number of loans \| Loan			1
Recorded Investment \| $			$ 8