SECURITIES - Summary of Amortized Cost and Fair Value of Securities Available for Sale (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 538,980	$ 648,230
Gross Unrealized Gains	12,260	5,037
Gross Unrealized Losses	(8,015)	(1,135)
Fair Value	543,225	652,132
Mortgage-backed securities: residential
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	286,307	374,923
Gross Unrealized Gains	8,369	1,876
Gross Unrealized Losses	(4)	(856)
Fair Value	294,672	375,943
Mortgage-backed securities: commercial
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	17,445	17,858
Gross Unrealized Gains	336	56
Gross Unrealized Losses	(86)	(134)
Fair Value	17,695	17,780
Corporate notes
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	4,500	32,825
Gross Unrealized Gains	108	539
Gross Unrealized Losses	(85)	(3)
Fair Value	4,523	33,361
State and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	230,728	222,624
Gross Unrealized Gains	3,447	2,566
Gross Unrealized Losses	(7,840)	(142)
Fair Value	$ 226,335	$ 225,048

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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