Securities - Available for Sale (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 531,307	$ 409,110
Unrealized Gain	1,994	4,798
Unrealized Loss	(10,967)	(4,199)
Securities available for sale	522,334	409,709
U.S. gov’t sponsored entities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	148,034	108,578
Unrealized Gain	178	478
Unrealized Loss	(2,703)	(908)
Securities available for sale	145,509	108,148
State & political subdivisions
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	137,848	134,428
Unrealized Gain	1,643	3,609
Unrealized Loss	(1,096)	(314)
Securities available for sale	138,395	137,723
Residential & multi-family mortgage
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	199,968	111,214
Unrealized Gain	76	304
Unrealized Loss	(5,409)	(1,882)
Securities available for sale	194,635	109,636
Corporate notes & bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	12,358	17,610
Unrealized Gain	31	52
Unrealized Loss	(353)	(462)
Securities available for sale	12,036	17,200
Pooled SBA
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	32,079	36,260
Unrealized Gain	66	355
Unrealized Loss	(1,312)	(575)
Securities available for sale	30,833	36,040
Other
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,020	1,020
Unrealized Gain	0	0
Unrealized Loss	(94)	(58)
Securities available for sale	$ 926	$ 962

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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-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
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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).

+ References

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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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-Publisher FASB
-Name Accounting Standards Codification
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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).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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