Real Estate Owned - Summary of Real Estate Owned Activity (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Real Estate Properties [Line Items]
Balance, beginning of year	$ 281
Sale of real estate owned	(266)
Loss on sale of real estate owned	(15)	$ 43
Balance, end of year	0	281
Commercial Properties [Member]
Real Estate Properties [Line Items]
Sale of real estate owned		(90)
Residential Properties [Member]
Real Estate Properties [Line Items]
Sale of real estate owned		(54)
Bank Properties [Member]
Real Estate Properties [Line Items]
Balance, beginning of year	281
Sale of real estate owned	(266)	(950)
Loss on sale of real estate owned	$ (15)
Balance, end of year		$ 281

The net gain (loss) resulting from sales and other disposals of real estate owned for investment purposes.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.14(d))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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- Definition

Amount of real estate investments sold for entities with a substantial portion of business acquiring and holding investment real estate.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 10
-Section S99
-Paragraph 6
-Subparagraph (SX 210.5-04.(c) Schedule III)
-URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 970
-SubTopic 360
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-28.4)
-URI http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024

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- Definition

Amount, before accumulated depreciation, of real estate investments for entities with a substantial portion of business acquiring and holding investment real estate.

+ References

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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.

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