Loans Receivable, Net - Troubled Debt Restructurings (Detail) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018 USD ($) SecurityLoan	Sep. 30, 2017 USD ($) SecurityLoan	Sep. 30, 2018 USD ($) SecurityLoan	Sep. 30, 2017 USD ($) SecurityLoan
Residential real estate
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan			2	1
Pre-modification Recorded Investment			$ 496
Post-modification Recorded Investment			$ 502
Recorded Investment				$ 665
Commercial Real Estate - Owner Occupied
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	1	1	1	4
Pre-modification Recorded Investment	$ 49	$ 700	$ 49	$ 3,309
Post-modification Recorded Investment	$ 50	$ 700	$ 50	$ 3,309
Commercial Real Estate - Investor
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	1	1	3	4
Pre-modification Recorded Investment	$ 171	$ 700	$ 1,395	$ 6,362
Post-modification Recorded Investment	$ 210	$ 700	$ 1,435	$ 6,484
Residential Real Estate
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan		2	2	6
Pre-modification Recorded Investment		$ 328	$ 257	$ 1,354
Post-modification Recorded Investment		$ 357	$ 270	$ 1,356
Commercial Real Estate - Investor, Subsequently Defaulted [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	0		1
Recorded Investment	$ 2,820		$ 2,820
Consumer, Subsequently Defaulted
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	0		1
Recorded Investment	$ 30		$ 30
Subsequently Defaulted
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan		0		0
Recorded Investment		$ 0		$ 0

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Financing Receivable Modifications Pre Modification Recorded Investment During Period

+ References

No definition available.

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- Definition

Trouble Debt Restructuring Modifications Recorded Investment

+ References

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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://fasb.org/us-gaap/role/ref/legacyRef
-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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