Consolidated Statements of Changes in Shareholders' Equity (Parenthetical) (USD $) In Thousands, except Per Share data	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010
Consolidated Statements of Changes in Shareholders' Equity
Net unrealized gains on securities arising during the period, taxes	$ 4,258	$ 1,599
Less: reclassification adjustment for net realized gains included in net income, taxes (tax benefits)	148
Net unrealized holding losses arising during the period, taxes (tax benefits)	(4)	(2,278)
Less: reclassification adjustment to net income, taxes (tax benefits)	(78)
Less: amortization of net loss, prior service gain and transition obligation included in net periodic benefit cost, taxes (tax benefits)	(3,513)	(1,932)
Less: reclassification adjustment for impact of D&Os of the PUC included in regulatory assets, taxes (tax benefits)	$ 3,875	$ 1,681
Common stock dividends (in dollars per share)	$ 0.93	$ 0.93

The amount of income taxes on the reclassification adjustments on pension and post retirement benefits for the accounting impact of the decisions issued by the Public Utilities Commission.

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- Definition

Tax effect on the reclassification adjustment for gains or losses realized upon the sale of securities during the period. Includes tax effect on other than temporary impairment 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 includes the portion attributable to the noncontrolling interest, if any.

+ Details

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- Definition

This element represents Less: reclassification adjustment to net income, taxes (tax benefits).

+ Details

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- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=6959260&loc=d3e187085-122770

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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 change in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

+ 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

+ Details

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