Deposits - Interest Expense On Deposits (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Banking and Thrift [Abstract]
Interest bearing checking	$ 52	$ 31
Money market	424	179
Statement savings accounts	74	61
Certificates of deposit	3,141	2,622
Total	$ 3,691	$ 2,893

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- Definition

Aggregate amount of interest expense on all deposits.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.6)
-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

+ Details

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- Definition

Amount of interest expense on domestic certificates of deposit liabilities.

+ References

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- Definition

Amount of interest expense on domestic checking deposit liabilities.

+ References

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- Definition

Amount of interest expense on domestic money market demand account deposit liabilities.

+ References

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- Definition

Amount of interest expense on domestic savings deposit liabilities.

+ References

+ Details

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