Investment Securities - Investments' Gross Unrealized Losses and Fair Value (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Available For Sale And Held To Maturity Securities In Continuous Unrealized Loss Position [Line Items]
Available-for-Sale, Less than 12 Months, Fair Value	$ 15,620	$ 69,120
Available-for-Sale, Less than 12 Months, Unrealized Losses	(101)	(1,558)
Available-for-Sale, 12 Months or More, Fair Value	26,112	271
Available-for-Sale, 12 Months or More, Unrealized Losses	(528)	(18)
Residential [Member]
Available For Sale And Held To Maturity Securities In Continuous Unrealized Loss Position [Line Items]
Available-for-Sale, Less than 12 Months, Fair Value	5,156	43,091
Available-for-Sale, Less than 12 Months, Unrealized Losses	(43)	(885)
Available-for-Sale, 12 Months or More, Fair Value	18,839
Available-for-Sale, 12 Months or More, Unrealized Losses	(246)
Commercial [Member]
Available For Sale And Held To Maturity Securities In Continuous Unrealized Loss Position [Line Items]
Available-for-Sale, Less than 12 Months, Fair Value	10,053	21,231
Available-for-Sale, Less than 12 Months, Unrealized Losses	(56)	(337)
Available-for-Sale, 12 Months or More, Fair Value	3,424	271
Available-for-Sale, 12 Months or More, Unrealized Losses	(54)	(18)
Obligations of States and Political Subdivisions [Member]
Available For Sale And Held To Maturity Securities In Continuous Unrealized Loss Position [Line Items]
Available-for-Sale, Less than 12 Months, Fair Value		1,050
Available-for-Sale, Less than 12 Months, Unrealized Losses		(2)
U.S. Treasury Securities [Member]
Available For Sale And Held To Maturity Securities In Continuous Unrealized Loss Position [Line Items]
Available-for-Sale, Less than 12 Months, Fair Value	0	3,748
Available-for-Sale, Less than 12 Months, Unrealized Losses	0	(334)
Available-for-Sale, 12 Months or More, Fair Value	3,849
Available-for-Sale, 12 Months or More, Unrealized Losses	(228)
Obligations of U.S. Government Sponsored Agencies [Member]
Available For Sale And Held To Maturity Securities In Continuous Unrealized Loss Position [Line Items]
Available-for-Sale, Less than 12 Months, Fair Value	411
Available-for-Sale, Less than 12 Months, Unrealized Losses	(2)
Available-for-Sale, 12 Months or More, Fair Value	0
Available-for-Sale, 12 Months or More, Unrealized Losses	0
Held-to-Maturity, Less than 12 Months, Fair Value	5,356	33,365
Held-to-Maturity, Less than 12 Months, Unrealized Losses	(16)	(1,685)
Held-to-Maturity, 12 Months or More, Fair Value	31,370
Held-to-Maturity, 12 Months or More, Unrealized Losses	$ (623)

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Available for sale securities continuous unrealized loss position less than twelve months aggregate losses accumulated in investments.

+ References

No definition available.

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- Definition

Available for sale securities continuous unrealized loss position twelve months or longer aggregate losses accumulated in investments.

+ References

No definition available.

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- Definition

Held-to-maturity securities continuous unrealized loss position less than twelve months accumulated loss.

+ References

No definition available.

+ Details

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- Definition

Held-to-maturity securities, continuous unrealized loss position twelve months or longer accumulated loss.

+ References

No definition available.

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- Definition

This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 6

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

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- Definition

This item represents the fair value of securities categorized as held-to-maturity that have been in a continuous unrealized loss position for less than twelve months.

+ References

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- Definition

This item represents the fair value of securities categorized as held-to-maturity securities that have been in a continuous unrealized loss position for twelve months or longer.

+ References

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