Securities (Carrying Amount, Unrecognized Gains and Losses and Fair Value of Securities Held-to-Maturity) (Detail) (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
Jun. 30, 2013	Dec. 31, 2012
Schedule of Held-to-maturity Securities [Line Items]
Carrying Amount	$ 268	$ 346
Fair Value	271	351
Obligations of State and Political Subdivisions [Member]
Schedule of Held-to-maturity Securities [Line Items]
Carrying Amount	268	346
Gross Unrealized Gains	3	5
Gross Unrealized Losses	0	0
Fair Value	$ 271	$ 351

Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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

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-Name Accounting Standards Codification

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Fair value of investments in debt securities classified as held-to-maturity.

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Amount of unrecognized gain before loss on investments in held-to-maturity securities.

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Amount of unrecognized loss before gain on investments in held-to-maturity securities. Excludes write-down for other than temporary impairment (OTTI).

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