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	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Unpaid Principal Balance
Total	$ 15,824		$ 15,824		$ 13,409
Recorded Investment
Total	15,915		15,915		13,352
Allowance for Loan and Lease Losses	415		415		243
Average Recorded Investment	15,976	$ 32,406	13,437	$ 36,989
Interest Income Recognized	59	280	148	1,021
Cash Basis Interest Recognized	48	287	140	1,022
SBA
Recorded Investment
Average Recorded Investment	378		126
Interest Income Recognized	0		0
Cash Basis Interest Recognized	0		0
Commercial \| Commercial and industrial
Unpaid Principal Balance
With no related allowance recorded	24		24		2,478
With an allowance recorded	475		475		0
Recorded Investment
With no related allowance recorded	23		23		2,429
With an allowance recorded	474		474		0
Allowance for Loan and Lease Losses	195		195		0
Average Recorded Investment	506	3,434	169	3,843
Interest Income Recognized	0	65	0	183
Cash Basis Interest Recognized	0	65	0	208
Commercial \| Commercial real estate
Recorded Investment
Average Recorded Investment		0		197
Interest Income Recognized		0		24
Cash Basis Interest Recognized		0		24
Commercial \| SBA
Unpaid Principal Balance
With no related allowance recorded	227		227		0
With an allowance recorded	161		161		0
Recorded Investment
With no related allowance recorded	221		221		0
With an allowance recorded	156		156		0
Allowance for Loan and Lease Losses	54		54		0
Commercial \| Construction
Recorded Investment
Average Recorded Investment	0		509
Interest Income Recognized	0		0
Cash Basis Interest Recognized	0		0
Commercial \| Lease financing
Unpaid Principal Balance
With an allowance recorded	41		41		0
Recorded Investment
With an allowance recorded	41		41		0
Allowance for Loan and Lease Losses	1		1		0
Average Recorded Investment	53		18
Interest Income Recognized	0		0
Cash Basis Interest Recognized	0		0
Consumer \| Single family residential mortgage
Unpaid Principal Balance
With no related allowance recorded	12,192		12,192		8,865
With an allowance recorded	2,337		2,337		1,772
Recorded Investment
With no related allowance recorded	12,288		12,288		8,887
With an allowance recorded	2,348		2,348		1,742
Allowance for Loan and Lease Losses	165		165		243
Average Recorded Investment	14,673	28,678	11,904	32,655
Interest Income Recognized	57	213	142	808
Cash Basis Interest Recognized	45	221	134	784
Consumer \| Other consumer
Unpaid Principal Balance
With no related allowance recorded	367		367		294
With an allowance recorded	0		0		0
Recorded Investment
With no related allowance recorded	364		364		294
With an allowance recorded	0		0		0
Allowance for Loan and Lease Losses	0		0		$ 0
Average Recorded Investment	366	294	711	294
Interest Income Recognized	2	2	6	6
Cash Basis Interest Recognized	$ 3	$ 1	$ 6	$ 6

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=84173941&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=84173941&loc=d3e5258-111524

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524

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