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Consolidated Statements of Income (Unaudited) (Parenthetical) (USD $) In Thousands, unless otherwise specified | 3 Months Ended
--- | ---
Mar. 31, 2013 | Mar. 31, 2012
Interest Expense |  |
Threshold limit of time deposits, minimum | $ 100,000 | $ 100,000
Unrealized net gains in available for sale securities | 95 | 44
Tax on reclassification adjustment | $ 33 | $ 15

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