Securities - Available for Sale (Detail) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 456,756	$ 409,110
Unrealized Gain	2,700	4,798
Unrealized Loss	(8,561)	(4,199)
Securities available for sale	450,895	409,709
U.S. Gov’t sponsored entities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	126,219	108,578
Unrealized Gain	253	478
Unrealized Loss	(2,040)	(908)
Securities available for sale	124,432	108,148
State & political subdivisions
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	132,734	134,428
Unrealized Gain	2,240	3,609
Unrealized Loss	(707)	(314)
Securities available for sale	134,267	137,723
Residential & multi-family mortgage
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	150,632	111,214
Unrealized Gain	64	304
Unrealized Loss	(4,229)	(1,882)
Securities available for sale	146,467	109,636
Corporate notes & bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	13,110	17,610
Unrealized Gain	36	52
Unrealized Loss	(291)	(462)
Securities available for sale	12,855	17,200
Pooled SBA
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	33,041	36,260
Unrealized Gain	107	355
Unrealized Loss	(1,209)	(575)
Securities available for sale	31,939	36,040
Other
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,020	1,020
Unrealized Gain	0	0
Unrealized Loss	(85)	(58)
Securities available for sale	$ 935	$ 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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-Publisher FASB
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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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