CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (Parenthetical) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
STATEMENTS OF COMPREHENSIVE INCOME
Amortization and reversal of net unrealized loss on securities transferred from available-for-sale to held-to-maturity, taxes	$ (29)	$ (122)	$ (91)
Reduction in non-credit component of otti charge, taxes	(16)	(16)	(137)
Non-credit component of OTTI charge recognized during the period, tax	0	0	3
Reclassification adjustment for securities sold during the period, taxes	450	50	461
Net unrealized securities gains arising during the period, tax	29	(162)	1,102
Defined benefit plan adjustments, tax	$ 2,685	$ (3,765)	$ (1,395)

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

No definition available.

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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.

+ References

No definition available.

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- Definition

Amount of tax (expense) benefit, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans, attributable to parent entity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 45

-Paragraph 20

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-SubTopic 10

-Section 50

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- Definition

Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale 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 (d)

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- Definition

Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

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- Definition

Amount of tax (expense) benefit of other than temporary impairment loss (OTTI) on investments in available-for-sale and held-to-maturity debt securities, recognized in other comprehensive loss and attributable to parent entity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 35

-Paragraph 34D

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