INVESTMENT SECURITIES - Investment Securities Held to Maturity (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Schedule Of Held To Maturity Securities [Line Items]
Held To Maturity Securities	$ 156,190	$ 161,483
Held To Maturity Securities Fair Value	132,241	131,544
US States And Political Subdivisions Member [Member] \| P R
Schedule Of Held To Maturity Securities [Line Items]
Held To Maturity Securities	156,190	161,483
Held To Maturity Securities Accumulated Unrecognized Holding Gain	0	0
Held To Maturity Securities Accumulated Unrecognized Holding Loss	23,949	29,939
Held To Maturity Securities Fair Value	$ 132,241	$ 131,544
Held To Maturity Securities Debt Maturities Average Yield	4.65%	4.62%
US States And Political Subdivisions Member [Member] \| After One To Five Years [Member] \| P R
Schedule Of Held To Maturity Securities [Line Items]
Held To Maturity Securities	$ 1,136	$ 1,371
Held To Maturity Securities Accumulated Unrecognized Holding Gain	0	0
Held To Maturity Securities Accumulated Unrecognized Holding Loss	27	37
Held To Maturity Securities Fair Value	$ 1,109	$ 1,334
Held To Maturity Securities Debt Maturities Average Yield	5.38%	5.38%
US States And Political Subdivisions Member [Member] \| After Five To Ten Years [Member] \| P R
Schedule Of Held To Maturity Securities [Line Items]
Held To Maturity Securities	$ 10,741	$ 11,523
Held To Maturity Securities Accumulated Unrecognized Holding Gain	0	0
Held To Maturity Securities Accumulated Unrecognized Holding Loss	782	1,041
Held To Maturity Securities Fair Value	$ 9,959	$ 10,482
Held To Maturity Securities Debt Maturities Average Yield	4.41%	4.25%
US States And Political Subdivisions Member [Member] \| After Ten Years [Member] \| P R
Schedule Of Held To Maturity Securities [Line Items]
Held To Maturity Securities	$ 144,313	$ 148,589
Held To Maturity Securities Accumulated Unrecognized Holding Gain	0	0
Held To Maturity Securities Accumulated Unrecognized Holding Loss	23,140	28,861
Held To Maturity Securities Fair Value	$ 121,173	$ 119,728
Held To Maturity Securities Debt Maturities Average Yield	4.66%	4.64%

Percentage of weighted average yield of held to maturity securities.

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- Definition

Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27232-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=65884222&loc=d3e22054-111558

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27232-111563

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.6)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Amount of accumulated unrealized gain on investments in debt securities classified as held-to-maturity.

+ References

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Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity.

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- Definition

Fair value of investments in debt securities classified as held-to-maturity.

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