LOANS AND LEASES AND ALLOWANCE FOR LOAN AND LEASE LOSSES - Loans and Leases Individually Evaluated for Impairment by Class of Loans (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Unpaid Principal Balance
Total	$ 13,403		$ 13,409
Recorded Investment
Total	13,395		13,352
Allowance for Loan and Lease Losses	250		243
Average Recorded Investment	13,472	$ 39,519
Interest Income Recognized	45	361
Cash Basis Interest Recognized	44	365
Commercial \| Construction
Unpaid Principal Balance
With no related allowance recorded	1,528		0
Recorded Investment
With no related allowance recorded	1,528		0
Average Recorded Investment	1,528
Interest Income Recognized	0
Cash Basis Interest Recognized	0
Commercial \| Commercial and industrial
Unpaid Principal Balance
With no related allowance recorded	0		2,478
Recorded Investment
With no related allowance recorded	0		2,429
Average Recorded Investment		4,596
Interest Income Recognized		63
Cash Basis Interest Recognized		88
Commercial \| Commercial real estate
Recorded Investment
Average Recorded Investment		305
Interest Income Recognized		10
Cash Basis Interest Recognized		10
Consumer \| Single family residential mortgage
Unpaid Principal Balance
With no related allowance recorded	9,097		8,865
With an allowance recorded	1,894		1,772
Recorded Investment
With no related allowance recorded	9,124		8,887
With an allowance recorded	1,860		1,742
Allowance for Loan and Lease Losses	250		243
Average Recorded Investment	11,055	34,324
Interest Income Recognized	43	286
Cash Basis Interest Recognized	43	265
Consumer \| Other consumer
Unpaid Principal Balance
With no related allowance recorded	884		294
Recorded Investment
With no related allowance recorded	883		$ 294
Average Recorded Investment	889	294
Interest Income Recognized	2	2
Cash Basis Interest Recognized	$ 1	$ 2

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953550-111524

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

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