Securities - Securities with Unrealized Loss Position (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Less than 12 Months
Fair Value	$ 58,267	$ 98,395
Unrealized Loss	(434)	(766)
12 Months or More
Fair Value	59,985	210,530
Unrealized Loss	(1,073)	(6,561)
Fair Value	118,252	308,925
Unrealized Loss	(1,507)	(7,327)
U.S. Gov’t sponsored entities
Less than 12 Months
Fair Value	7,040	14,786
Unrealized Loss	(3)	(41)
12 Months or More
Fair Value	14,989	70,676
Unrealized Loss	(16)	(1,529)
Fair Value	22,029	85,462
Unrealized Loss	(19)	(1,570)
State & political subdivisions
Less than 12 Months
Fair Value	826	13,834
Unrealized Loss	(5)	(62)
12 Months or More
Fair Value	684	21,080
Unrealized Loss	(97)	(511)
Fair Value	1,510	34,914
Unrealized Loss	(102)	(573)
Residential & multi-family mortgage
Less than 12 Months
Fair Value	41,841	69,015
Unrealized Loss	(346)	(656)
12 Months or More
Fair Value	32,555	87,286
Unrealized Loss	(539)	(2,917)
Fair Value	74,396	156,301
Unrealized Loss	(885)	(3,573)
Corporate notes & bonds
Less than 12 Months
Fair Value	0	0
Unrealized Loss	0	0
12 Months or More
Fair Value	4,718	9,759
Unrealized Loss	(282)	(601)
Fair Value	4,718	9,759
Unrealized Loss	(282)	(601)
Pooled SBA
Less than 12 Months
Fair Value	8,560	760
Unrealized Loss	(80)	(7)
12 Months or More
Fair Value	6,075	20,795
Unrealized Loss	(83)	(917)
Fair Value	14,635	21,555
Unrealized Loss	(163)	(924)
Other
Less than 12 Months
Fair Value	0	0
Unrealized Loss	0	0
12 Months or More
Fair Value	964	934
Unrealized Loss	(56)	(86)
Fair Value	964	934
Unrealized Loss	$ (56)	$ (86)

Debt Securities, Available-for-sale, Unrealized Loss Position Less Than 12 Months [Abstract]

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Debt Securities, Available-for-sale, Unrealized Loss Position More Than 12 Months [Abstract]

+ References

No definition available.

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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), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118955579&loc=SL82922890-210455

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
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-Publisher FASB
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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ 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), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
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-Publisher FASB
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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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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), in unrealized loss position without allowance for credit loss.

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