Securities - Gains and Losses on Sales of Securities Available for Sale (Detail) (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Amortized Cost And Fair Value Debt Securities [Abstract]
Gross gains on sales of securities	$ 8	$ 353	$ 353
Gross losses on sales of securities	(2)	(182)	(182)
Net realized gains on sales of securities available for sale	6	171	171
Sales proceeds	$ 69,768	$ 31,340	$ 36,669

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This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27357-111563

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- Definition

This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

+ Details

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- Definition

This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

+ Details

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- Definition

The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 11

-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26853-111562

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-Subparagraph (a),(b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585

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