Securities - Securities Available for Sale (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Amortized cost	$ 533,203	$ 521,337
Unrealized gains	10,617	2,853
Unrealized losses	(1,507)	(7,327)
Fair value	542,313	516,863
U.S. Gov’t sponsored entities
Debt Securities, Available-for-sale [Line Items]
Amortized cost	124,189	134,010
Unrealized gains	2,924	254
Unrealized losses	(19)	(1,570)
Fair value	127,094	132,694
State & political subdivisions
Debt Securities, Available-for-sale [Line Items]
Amortized cost	101,177	134,662
Unrealized gains	3,288	1,942
Unrealized losses	(102)	(573)
Fair value	104,363	136,031
Residential & multi-family mortgage
Debt Securities, Available-for-sale [Line Items]
Amortized cost	273,404	209,126
Unrealized gains	4,117	500
Unrealized losses	(885)	(3,573)
Fair value	276,636	206,053
Corporate notes & bonds
Debt Securities, Available-for-sale [Line Items]
Amortized cost	8,350	12,356
Unrealized gains	14	22
Unrealized losses	(282)	(601)
Fair value	8,082	11,777
Pooled SBA
Debt Securities, Available-for-sale [Line Items]
Amortized cost	25,063	30,163
Unrealized gains	274	135
Unrealized losses	(163)	(924)
Fair value	25,174	29,374
Other
Debt Securities, Available-for-sale [Line Items]
Amortized cost	1,020	1,020
Unrealized gains	0	0
Unrealized losses	(56)	(86)
Fair value	$ 964	$ 934

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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