INVESTMENTS (Amortized Cost and Estimated Fair Values of Investments Held-To-Maturity) (Detail) $ in Thousands	Dec. 31, 2015 USD ($)
Schedule Of Held To Maturity Securities [Line Items]
Amortized Cost	$ 208,265
Gross Unrealized Gains	4,320
Gross Unrealized Losses	(881)
Investments held-to-maturity, fair value	211,704
U.S. Government Agencies
Schedule Of Held To Maturity Securities [Line Items]
Amortized Cost	56,460
Gross Unrealized Gains	0
Gross Unrealized Losses	(733)
Investments held-to-maturity, fair value	55,727
State and municipal
Schedule Of Held To Maturity Securities [Line Items]
Amortized Cost	149,537
Gross Unrealized Gains	4,297
Gross Unrealized Losses	(148)
Investments held-to-maturity, fair value	153,686
Mortgage-Backed
Schedule Of Held To Maturity Securities [Line Items]
Amortized Cost	168
Gross Unrealized Gains	23
Gross Unrealized Losses	0
Investments held-to-maturity, fair value	191
Corporate Debt
Schedule Of Held To Maturity Securities [Line Items]
Amortized Cost	2,100
Gross Unrealized Gains	0
Gross Unrealized Losses	0
Investments held-to-maturity, fair value	$ 2,100

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

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

+ References

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

+ References

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Fair value 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 (aa)
-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 50
-Paragraph 5
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27232-111563

Reference 3: 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

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