UNAUDITED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (Parenthetical) (USD $) In Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
STATEMENTS OF COMPREHENSIVE INCOME
Amortization and reversal of net unrealized loss on securities transferred from available-for-sale to held-to-maturity, taxes	$ 12	$ 12	$ 38	$ 41
Reduction in non-credit component of OTTI charge, taxes	4	601	570	905
Non-credit component of OTTI charge recognized during the period, tax	(11)	(99)	(11)	(126)
Reclassification adjustment for securities sold during the period, taxes	10	0	10	384
Net unrealized securities gains arising during the period, tax	(494)	(348)	(457)	131
Defined benefit plan adjustments, tax	$ 0	$ 0	$ 23	$ (560)

Tax effect of the reduction in non-credit component of other than temporary impairment (OTTI).

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- Definition

Tax effect of the amortization of the unrealized holding gain(loss) at the date of the transfer for debt securities transferred from available-for-sale category to the held-to-maturity category.

+ Details

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- Definition

Tax effects of the increase (decrease) to accumulated comprehensive income during the period related to benefit plans. While for technical reasons this element has no balance attribute, the default assumption is a credit balance consistent with its label.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 130

-Paragraph 25

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=6920043&loc=d3e640-108580

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 38

-Subparagraph c(3)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Tax effect on the reclassification adjustment for gains or losses realized upon the sale of securities during the period.

+ References

+ Details

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- Definition

Tax effect on gross appreciation or the gross loss in value of the total of unsold securities during the period being reported on.

+ References

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- Definition

The tax effect related to other than temporary impairment (OTTI) loss on a debt security, categorized as either Available-for-sale or Held-to-maturity, related to factors other than credit losses when the entity does not intend to sell the security and it is not more likely than not that the entity will be required to sell the security before recovery of its amortized cost basis. This amount is the portion of the tax effect on other than temporary losses related to investments in debt securities categorized as Available-for-sale or Held-to-maturity which are attributable to the parent.

+ References

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

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS115-1/124-1

-Paragraph 15D

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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