Loans Receivable, Net - Troubled Debt Restructurings (Detail) $ in Thousands	3 Months Ended
Mar. 31, 2018 USD ($) SecurityLoan	Mar. 31, 2017 USD ($) SecurityLoan
Residential Real Estate
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	2	2
Pre-modification Recorded Investment	$ 257	$ 368
Post-modification Recorded Investment	$ 270	$ 341
Commercial Real Estate - Owner Occupied
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan		2
Pre-modification Recorded Investment		$ 1,643
Post-modification Recorded Investment		$ 1,643
Commercial Real Estate - Investor
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	1	1
Pre-modification Recorded Investment	$ 179	$ 626
Post-modification Recorded Investment	$ 180	$ 773
Subsequently Defaulted
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	0	1
Recorded Investment	$ 0	$ 188
Commercial and industrial
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	1
Pre-modification Recorded Investment	$ 237
Post-modification Recorded Investment	$ 243

Financing Receivable Modifications Post Modification Recorded Investment During Period

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Financing Receivable Modifications Pre Modification Recorded Investment During Period

+ References

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- Definition

Trouble Debt Restructuring Modifications Recorded Investment

+ References

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- Definition

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+ References

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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